Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
cob19421_es.indd Sec1:2 12/22/08 9:52:54 PM user-s178 cob19421_es.indd PagePage Sec1:2 12/22/08 9:52:54 PM user-s178 /Users/user-s178/Desktop/22:12:08 /Users/user-s178/Desktop/22:12:08 Special Constants Special Constants � � � 3.1416 � ��3.1416 � 2.7183 e � e2.7183 Formulas from Analytical Geometry: 1 S 2 S Formulas from Analytical Geometry: P1 PS (x1(x , y11,),y1P),2 PS (x2(x , y22,)y2) � � � � � 3.1416 � 3.1416 2 2 � � � 1.0472 � 1.0472 3 3 � 1.4142 12 12 � 1.4142 � 1.7321 13 13 � 1.7321 � � � 0.5236 � 0.5236 6 6 13 13 � 0.8660 � 0.8660 2 2 � � � 0.7854 � 0.7854 4 4 12 12 � 0.7071 � 0.7071 2 2 � � � 0.2618 � 0.2618 12 12 13 13 � 0.5774 � 0.5774 3 3 Distance between 1 and Distance between P1 P and P2 P2 Special Products Special Products 2 2 � b21a 1a �1ab21a � b2��b2a2��a b2� b 2 2 2 2 b2 2 � 2ab 1a �1ab2� � a ��a 2ab � b2� b 3 3 2 2 3 3 b2 3 � 23ab 1a �1ab2� � a ��a 3a�2b3a� b3ab � b3� b 2 �� b2xab��ab1x��1xa21x � a21x x2 �x 1a��1ab2x � b2� b2 2 2 2 2 b2 � 2ab a2 �a 2ab � b2��b 1a��1ab2� 2 2 � b21a a2 �a b2��b 1a��1ab21a � b2� b2 2 2 2 2 b2 � 2ab a2 �a 2ab � b2��b 1a��1ab2� Special Factorizations Special Factorizations � � 3 3 2 2 3 2 1a � ab 2 a3 �a b3��b 1a��1ab2�1ab2 � ab � b �2 b 2 3 2 Rectangle Rectangle 2 � b21a a3 �a b3��b 1a��1ab21a � ab��abb2�2 b 2 Parallelogram Parallelogram A �Abh� bh w w � 2w P �P2l��2l2w A �Alw� lw h Triangle Triangle Trapezoid Trapezoid h Right Triangle Right Triangle B B of angles SumSum of angles A A A � B � C � 180° A � B � C � 180° C Ellipse Ellipse � �ab A �A�ab 2 2 2 � 221a C �C�� 221a � b2�2 b 2 a c Pythagorean Theorem C Pythagorean Theorem 2 2 2 a2 �a b2��b c2� c b 1 1 bh bh A �A � 2 2 c a a a 4 4 ab ab A �A � 3 3 a b b b b r 3 � lwh V �Vlwh � wh S � Slw��lwlh��lhwh V �Vs3� s 2 S � S6s�2 6s Right Circular Cone Right Circular Cone Right Square Pyramid Right Square Pyramid 1 12 �r2h V �V � �r h 3 3 �1r�r S � S�r �1rs2� s2 CoburnAlg&Trig2e10lbj_SE_ES.indd 1 ISBN: 0073519529 & 0073519421 Front Author: Coburn 0-4-4-4 ISBN: 0-07-351942-1 Front endsheets ISBN: 0-07-351942-1 Front endsheets Title: Algebra & Trig and Precalculus, Author: John W. Coburn Color: Author: John W. Coburn Color: 5 5 2e Title: College Precalculus, 2e Pages: Title: College Precalculus, 2e Pages: 2, 32, 3 1 2 1 b2h V �V � bh 3 3 2 2 2 2 � b2b S � Sb2��b b2b � 4h�2 4h Dependent (Coincident) Lines Dependent (Coincident) Lines Slopes Unequal: m1m� m2 Slopes Are Are Unequal: m1 � 2 Slopes y-Intercepts Equal: m1m�, m 2, b1 � b2 Slopes and and y-Intercepts Are Are Equal: m1 � 2 b1 � b2 y y b � x � log bx 3 y � ylog bx 3 b � x logblog b �b b1 � 1 x bbx� x logblog bx � blogbbx � x � x M M � log M � log N b b logblogb�Nlog b M � logb N N nt r a1r � b nb A �AP� a1P� n 1 logblog 1 �b 10 � 0 x bx logblog logc log x �c x � log c log c b logb x b # M P�# log P log bM logblog MPb� bM P S initial deposit, S periodic payment P SPinitial deposit, p Spperiodic payment r r S interest per time period R SRinterest rate rate per time period a ba n b n nt Accumulated Value of an Annuity Accumulated Value of an Annuity p p �11 �nt R2 nt � 1� A �A ��11R� R2 � 1� R Sequences Series: Sequences andand Series: � � S compounding periods/year n Sncompounding periods/year S time in years t S ttime in years Interest Compounded Continuously Interest Compounded Continuously �rt Pert A �APe Payments Required to Accumulate Amount Payments Required to Accumulate Amount A A AR AR p � p � 11 �nt R2 nt � 1 11 � R2 � 1 Sterm, 1st term, S term, nth term, S sum n terms, S common difference, S common a1 Sa11st an Sannth Sn SSnsum of n of terms, d Sdcommon difference, r Srcommon ratioratio b Formulas from Solid Geometry: SS surface area, VS volume Formulas from Solid Geometry: SS surface area, VS volume Cube Cube Intersecting Lines Intersecting Lines 1 Interest Compounded n Times Interest Compounded n Times perper YearYear r � � Rectangular Solid Rectangular Solid Slopes a Product of �1: 1m2 � �1 Slopes HaveHave a Product of �1: m1mm 2 � �1 S interest per year r Srinterest rate rate per year b a a Slopes Equal: m1m� m2 Slopes Are Are Equal: m1 � 2 S amount accumulated A SAamount accumulated h h Right Parabolic Segment Right Parabolic Segment a Perpendicular Lines Perpendicular Lines � log b M � logb N logblog MNb MN � log b M � logb N �2 �r2 A �A�r � 2�r � �d C �C2�r � �d b Parallel Lines Parallel Lines 1 Applications Exponentials Logarithms Applications of of Exponentials andand Logarithms Circle Circle a Slope-Intercept (slope m, y-intercept Slope-Intercept FormForm (slope m, y-intercept b) b) �� mxb,�where b, where � mx1 y � ymx b � by ��y1mx � � Triangle Triangle a Point-Slope Point-Slope FormForm � m1x y � yy ��y1m1x � x �2 x1 2 � � s P �Pns� ns a aP A �A � P 2 2 h h h h 1a � b2 A �A � 1a 2� b2 b b 2 b b Regular Polygons Regular Polygon s s P �P4s� 4s 2 A �As2� s l l Square Square Equation of Line Containing 1 and Equation of Line Containing P1 P and P2 P2 Logarithms Logarithmic Properties Logarithms andand Logarithmic Properties 2 Formulas from Plane Geometry: PS perimeter, CS circumference, AS area Formulas from Plane Geometry: PS perimeter, CS circumference, AS area � � Equation of Line Containing 1 and Equation of Line Containing P1 P and P2 P2 1 3 3 2 2 3 3 b2 3 � 23ab 1a �1ab2� � a ��a 3a�2b3a� b3ab � b3� b ¢y ¢yy2��y2y1� y1 m �m � � ¢x ¢xx2 �x2x1� x1 2 2 � 21x 2 �2 x1 2 � 1y2 �2 y1 2 d � d21x 2 � x1 2 � 1y2 � y1 2 � � 2 �� b2xab� ab 1x �1xa2�1x a2 �1xb2��b2x2��x 1a��1ab2x 2 2 2 2 b2 2 � 2ab 1a �1ab2� � a ��a 2ab � b2� b Slope of Line Containing 1 and Slope of Line Containing P1 P and P2 P2 Right Circular Cylinder Right Circular Cylinder �2h�r2h V �V�r � 1r 2�r S � S2�r �1rh2� h2 Sphere Sphere 4 34 �r3 V �V � �r 3 3 � 24�r2 S � S4�r Arithmetic Sequences Arithmetic Sequences Geometric Sequences Geometric Sequences � .2d, � 12d a1, aa21,�a2a1��a1d,�a3d,�a3a1��a12d, . . ,. a. n. ,�ana1��a11n��1n12d n n 1a1a �2 an 2 Sn �Sn � 1a1 � n 2 2 n n � 12d� �2a1 �2a � 11n��1n12d� Sn �Sn � 2 2 2 a1rn�1 a1, aa21,�a2a1�r, aa13r,�a3a1�r2,a.1r. ., ,. a. n. ,�ana1�rn�1 n a1 �a1a1�rna1r Sn �Sn � 1 � r 1�r a1 a1 ; �r� 6 1 S � Sq �q 1 ;��r�r 6 1 1�r Binomial Theorem Binomial Theorem � � n n 0 n n n�1 1 n n n�2 2 n n 0 n n n 1 n�1 n # # a � na ba n b2 � 1 ba n b b ab1 �b a �b aan�2 b ab2 �b # �# # # � a0bba 1a �1ab2� � a b aan0bb0a�b a�b aan�1 bn�1b � a �ba 1 2 n � 1 0 1 2 n�1 n n # # 132122112 a n b a�n b � n! n! ; ; 0! �0!1� 1 �� n1n121n � 121n # # #132122112 n! �n!n1n � 22�# 22 � k2! k k k!1n k!1n � k2! 1/8/09 2:41:04 PM cob19421_es.indd Page Sec1:3 12/22/08 9:52:56 PM user-s178 � /Users/user-s178/Desktop/22:12:08 The Toolbox and Other Functions linear � linear y y identity constant y y � mx � b y Fundamental Counting Principle: Given an experiment with two tasks completed in sequence, if the first can be completed in m ways and the second in n ways, the experiment can be completed in m � n ways. y�b y�x Permutations—Order Is a Consideration: (Al, Bo, Ray) and (Ray, Bo, Al) finish the race in a different order. n! . The permutations of r objects selected from a set of n (unique) objects is given by nPr � (n � r)! Combinations—Order Is Not a Consideration: (Al, Bo, Ray) and (Ray, Bo, Al) form the same committee. n! . The combinations of r objects selected from a set of n (unique) objects is given by nCr � r!(n � r)! Basic Probability: Given S is a sample space of equally likely events and E is an event defined relative to S. n(E) , where n1E2 and n1S2 represent the number of elements in each. The probability of E is P(E) � n(S) For any event E1: 0 � P1E1 2 � 1 and P1E1 2 � P1~E1 2 � 1. (0, b) (0, b) x x x y � mx � b squaring y m � 0, b � 0 cubing y square root y y y � x2 y � �x� x y � x3 y � �x x cube root x floor function reciprocal quadratic y � 1 x P1E1 � E2 2 � P1E1 2P1E2 2 P1E1 ´ E2 2 � P1E1 2 � P1E2 2 � P1E1 � E2 2 y y circle with center at (h, k) 1 y � x2 3 y � �x r x 1 2 x x x k exponential exponential y logarithmic y bx x2 y�c y � b�x y � logb x y� x h � y2 � (�a, 0) � (c, 0) 1 x (0, 1 �c a ) vertical reflections vertical stretches/compressions S y � af 1x � h2 � k S y � f 1x2 S Transformation of Given Function horizontal shift h units, opposite direction of sign vertical shift k units, same direction as sign hyperbola with center at (h, k) k (h, k) central hyperbola (x � h)2 a2 � (y � k)2 b2 (0, b) � y2 b2 �1 �1 x If a � b, the ellipse is oriented vertically. x2 a2 � y2 b2 p�0 ( p, 0) x (0, p) �1 x x If term containing y leads, the hyperbola is oriented vertically. (0, �b) y x2 � 4py vertical parabola focus (0, p) directrix y � �p y y � �p (c, 0) h For linear function models, the average rate of change on the interval 3 x1, x2 4 is constant, and given by the slope formula: ¢y y2 � y1 � . The average rate of change for other function models is non-constant. By writing the slope formula in function form x2 � x1 ¢x using y1 � f 1x1 2 and y2 � f 1x2 2, we can compute the average rate of change of other functions on this interval: (y � k)2 b2 c2 � |a2 � b2| (�c, 0) Average Rate of Change of f(x) � (a, 0) x2 a2 x Transformations of Basic Graphs Given Function (h � a, k) (x � h)2 a2 h c 1 � ae�bx y � (�c, 0) (0, � b) x x ellipse with center at (h, k), a � b (0, b) r2 1 1 (h, k) (h, k � b) central ellipse (x, y) (0, 0) y y (h � a, k) (x � h)2 � (y � k)2 � r2 r logistic k (h, k � b) (h, k) central circle y� Probability of E1 or E2 Conic Sections y y� Probability of E1 and E2 x reciprocal y y � �x� y x m � 1, b � 0 m � 0, b � 0 m � 0, b � 0 absolute value Quick Counting and Probability p�0 x � �p y2 � 4px horizontal parabola focus ( p, 0) directrix x � �p �1 c2 � a2 � b2 f(x2) � f(x1) �y � �x x2 � x1 CoburnAlg&Trig2e10lbj_SE_ES.indd 2 ISBN: 0073519529 & 0073519421 Author: Coburn ISBN: 0-07-351942-1 Title: Algebra & Trig and Precalculus, Author: John W. Coburn 2e Title: College Precalculus, 2e 1/8/09 2:41:04 PM Front 0-4-4-4 Back endsheets Color: 5 Pages: 4, 5 cob19421_es.indd Page Sec1:3 12/22/08 9:52:56 PM user-s178 � /Users/user-s178/Desktop/22:12:08 The Toolbox and Other Functions linear � linear y y identity constant y y � mx � b y Fundamental Counting Principle: Given an experiment with two tasks completed in sequence, if the first can be completed in m ways and the second in n ways, the experiment can be completed in m � n ways. y�b y�x Permutations—Order Is a Consideration: (Al, Bo, Ray) and (Ray, Bo, Al) finish the race in a different order. n! . The permutations of r objects selected from a set of n (unique) objects is given by nPr � (n � r)! Combinations—Order Is Not a Consideration: (Al, Bo, Ray) and (Ray, Bo, Al) form the same committee. n! . The combinations of r objects selected from a set of n (unique) objects is given by nCr � r!(n � r)! Basic Probability: Given S is a sample space of equally likely events and E is an event defined relative to S. n(E) , where n1E2 and n1S2 represent the number of elements in each. The probability of E is P(E) � n(S) For any event E1: 0 � P1E1 2 � 1 and P1E1 2 � P1~E1 2 � 1. (0, b) (0, b) x x x y � mx � b absolute value squaring y m � 0, b � 0 cubing y square root y y� y � �x� y x2 x y� x3 y � �x x cube root x floor function reciprocal quadratic y � Probability of E1 or E2 P1E1 � E2 2 � P1E1 2P1E2 2 P1E1 ´ E2 2 � P1E1 2 � P1E2 2 � P1E1 � E2 2 Conic Sections y y y� Probability of E1 and E2 x reciprocal y y � �x� y x m � 1, b � 0 m � 0, b � 0 m � 0, b � 0 Quick Counting and Probability 1 x y� 3 y circle with center at (h, k) 1 x2 y � �x r x 1 2 x x x k exponential y logarithmic y y � bx y � logb x y� x h (�a, 0) 1 x (0, 1 �c a ) � x2 a2 x vertical reflections vertical stretches/compressions S y � af 1x � h2 � k S y � f 1x2 S Transformation of Given Function horizontal shift h units, opposite direction of sign vertical shift k units, same direction as sign hyperbola with center at (h, k) k (h, k) central hyperbola (x � h)2 a2 � y2 b2 �1 �1 x If a � b, the ellipse is oriented vertically. (y � k)2 b2 (c, 0) x2 a2 � c2 � y2 b2 p�0 ( p, 0) x (0, p) �1 x x If term containing y leads, the hyperbola is oriented vertically. (0, �b) y x2 � 4py vertical parabola focus (0, p) directrix y � �p y y � �p h For linear function models, the average rate of change on the interval 3x1, x2 4 is constant, and given by the slope formula: ¢y y2 � y1 � . The average rate of change for other function models is non-constant. By writing the slope formula in function form x ¢x 2 � x1 using y1 � f 1x1 2 and y2 � f 1x2 2, we can compute the average rate of change of other functions on this interval: � (0, b) (�c, 0) Average Rate of Change of f(x) (y � k)2 b2 c2 � |a2 � b2| Transformations of Basic Graphs Given Function � (a, 0) h y � (c, 0) (0, � b) x x (�c, 0) c 1 � ae�bx 1 1 (h � a, k) (0, b) x2 � y2 � r2 y�c y � b�x (x, y) ellipse with center at (h, k), a � b (x � h)2 a2 (h, k � b) central ellipse (0, 0) y y (h, k) (x � h)2 � (y � k)2 � r2 r logistic (h � a, k) (h, k) central circle exponential k (h, k � b) p�0 x � �p y2 � 4px horizontal parabola focus ( p, 0) directrix x � �p �1 a2 � b2 f(x2) � f(x1) �y � �x x2 � x1 CoburnAlg&Trig2e10lbj_SE_ES.indd 3 ISBN: 0073519529 & 0073519421 Author: Coburn ISBN: 0-07-351942-1 Title: Algebra & Trig and Precalculus, Author: John W. Coburn 2e Title: College Precalculus, 2e 1/8/09 2:41:05 PM Back 4-4-4-0 Back endsheets Color: 5 Pages: 4, 5 cob19421_es.indd Sec1:4 12/22/08 9:52:57 PM user-s178 cob19421_es.indd PagePage Sec1:4 12/22/08 9:52:57 PM user-s178 /Users/user-s178/Desktop/22:12:08 /Users/user-s178/Desktop/22:12:08 Commonly used, small case Greek letters Commonly used, small case Greek letters Fundamental Identities Fundamental Identities � � � � alpha alpha betabeta gamma gamma deltadelta � � zeta zeta thetatheta lamda lamda mu mu pi pi rho rho sigma sigma phi phi psi psi omega omega epsilon epsilon Trigonometric Functions a Real Number Trigonometric Functions of of a Real Number � � Reciprocal Identities Reciprocal Identities Ratio Identities Ratio Identities Pythagorean Identities Pythagorean Identities 1 1 sec sec � � cos cos sin sin tan tan � � cos cos �2cos �21 � 1 sin2sin�2cos sin1�2 � �sin sin1�2 � �sin 1 1 csc csc � � sin sin cos cos cot cot � � sin sin �2sec2 �2tan�2sec 1 � 1tan cos1�2 � cos cos1�2 � cos �2cot�2csc �2csc2 1 � 1cot tan1�2 � �tan tan1�2 � �tan t t (x, y)(x, y) number on unit the unit circle associated P1x,P1x, y2 ony2 the For For any any real real number t andt and pointpoint circle associated withwith t: t: y y ; x0 � 0 cos tcos � tx � x sint sint � y� y tan t tant � � ;x� x x 1 1 1 1 x x ; x0 � 0 ; y0 � 0 ; y0 � 0 sectsect � � csctcsc �t� ;y� ;y� ;x� cot tcot �t� x x y y y y 1 1 cot cot � � tan tan r � 1r � 1 Cofunction Identities Cofunction Identities 1 1 Trigonometry Coordinate Plane Trigonometry andand thethe Coordinate Plane x x cos cos � � r r y y sin sin � � r r y y , x0 � 0 tan tan � � ,x� x x r r , x0 � 0 sec sec � � ,x� x x r r , y0 � 0 csc csc � � ,y� y y x x , y0 � 0 ,y� cot cot � � y y a xb��xbcscx � cscx sec asec � 2 2 r r y y 5 5 (x, y)(x, y) a point on terminal the terminal an angle in standard position: P1x,P1x, y2 a y2point in standard For For on the side side of anofangle position: a xb��xbcot �xcot x tan atan � 2 2 y y � � r r �5 �5 5 x 5 x x Sum Difference Identities Sum andand Difference Identities � � � xcos x sin asina � xb��xbcos 2 2 x � � �xsin x � xb��xbsin cosacosa 2 2 cos1 � cos � sin cos1 � 2��2cos coscos� sin sinsin �xtan x a xb��xbtan cot acot � 2 2 � tan tantan � tan tan1 tan1 � 2��2 � � tan tan 1 �1 tantan Double-Angle Identities Double-Angle Identities Half-Angle Identities Half-Angle Identities 2 Right Triangle Trigonometry Right Triangle Trigonometry �5 2 � 2cos � 2cos �21 � 1 �5 2 � 2sin 2 � 1� � 12sin indicated adjacent opposite to acute angle ¢ABC For For rightright ¢ABC withwith indicated sidessides adjacent and and opposite to acute angle : : adj adj coscos � � hyp hyp opp opp sinsin � � hyp hyp opp opp tan tan � � adj adj hyp hyp sec sec � � adj adj hyp hyp csccsc � � opp opp adj adj cotcot � � opp opp hyp hyp opp opp � 122 cos 122 1 � 1cos sin2sin�2 � 2 2 � cos 1 � 1cos cos cos � �� � 2 2 A A2 2 � 122 cos 122 1 � 1cos �2 � cos2cos 2 2 Product-to-Sum Identities Product-to-Sum Identities Special Triangles Special Angles Special Triangles andand Special Angles B 0° 0° 0 0 1 1 0 0 1 13 1 30° 30° 1 2 1 2 13 2 13 2 1 13 45° 45° 12 2 12 2 12 2 12 2 1 60° 60° 13 2 13 2 1 2 1 2 90° 90° 1 1 0 0 — — 2 2 12 12 13 13 2 13 2 13 — — 1 1 1 1 — — 2 13 2 13 13 13 12 12 2 2 — — B B 1 1 1 13 1 13 0 0 60� 60� 45� 45� √2x √2x A 45� A 45� 1x 1x B 2x 2x 1x 1x C C A 30� 30� A √3x √3x 1 y �t csc t y � csc y 1 1 1 2 �1 �1 2 3 2 3 2 y 1 y C C 1 1 �cos1 � cos1 � 2� �cos1 � 2��2cos1 � 2� cos cos coscos � � 2 2 2 t2 t �1 �1 CoburnAlg&Trig2e10lbj_SE_ES.indd 4 ISBN: 0073519529 & 0073519421 Back Author: Coburn 4-4-4-0 ISBN: 0-07-351942-1 Front endsheets ISBN: 0-07-351942-1 endsheets Title: Algebra & Trig and Precalculus, Front Author: John W. Coburn Color: 5 Author: John W. Coburn Color: 5 2e Title: College Precalculus, Pages: Title: College Precalculus, 2e 2e Pages: 6, 76, 7 2 �� �� �sin 2 cosa b sinbasin a b b sin sin �sin �2 � cosa 2 2 2 2 �� �� b cosa b b � cos 2 cosa b cosa cos cos �cos �2 � cosa 2 2 2 2 � 4 , 1�� 4 , 3 2 3 2 2 t2 t � � � 2 2 �2 �1 �1 2 � � 1� �� �� b sina b b � cos � sina �2 sin a b sina cos cos �cos ��2 2 2 2 2 Sines LawLaw of of Sines y �t tan t y � tan 1 y �tcos t y � cos 2 �� �� bcosa b b �sin 2 sina bcosa sin sin �sin �2 � sina 2 2 2 2 1 1 �cos1 � cos1 � 2� sin sin sinsin � � �cos1 � 2��2cos1 � 2� 2 2 y y �t sec t y � sec y �t sin t y � sin 1 1 �sin1 � sin1 � 2� �sin1 � 2��2sin1 � 2� sin sin coscos � � 2 2 1 1 �sin1 � sin1 � 2� �sin1 � 2��2sin1 � 2� cos cos sinsin � � 2 2 Graphs Trigonometric Functions Graphs of of thethe Trigonometric Functions y � � 1x 1x � � y Sum-to-Product Identities Sum-to-Product Identities � � � sin �sin� cos �cos � tan�tan� csc �csc � sec �sec � cot �cot � C C sin Asin Asin Bsin Bsin Csin C � � � � a a b b c c 3 2 t 3 t y �t cot t y � cot 2 Area a Triangle Area of of a Triangle � � 1 1 bcAsin A A �A � bc sin 2 2 � 122 cos 122 1 � 1cos tan2tan�2 � � 122 cos 122 1 � 1cos sin sin � � � cos 1 � 1cos adj adj � � � � cos 1 � 1cos � � tan tan 2 2 sin sin 2 tan2tan tan122 tan122 � � �2 tan 1 � 1tan 2 � � � cos 1 � 1cos sin sin � �� � 2 2 A A2 2 2 cos122 � cos � sin cos122 � cos �sin � � Power Reduction Identities Power Reduction Identities � � sin122 � 2sin sin122 � 2sin coscos 2 �sin � cos sin1sin1 � 2��2sin coscos �cos sinsin �xsec x a xb��xbsec csc acsc � 2 2 � � 2 Identities to Symmetry Identities duedue to Symmetry b A � 2bc cos A a2 �a2b2��b2c2��c22bc cos A b A a c c B Cosines LawLaw of of Cosines � � a � 2ac cos B b2 �b2a2��a2c2��c22ac cos B � 2ab cos C c2 �c2a2��a2b2��b22ab cos C B 1/8/09 2:41:06 PM