# Cos^2A/sinA-cosecA+sinA=0 Prove lHS =RHS

8,328 results
1. ## maths

Prove SinA/1-CosA = CosecA + CotA

2. ## Pre-Calculus

If sinA=3/5 when pi/2 < A < pi and cosB=5/13 when 3pi/2 < B < 2pi, find the exact value of the function cos(5pi/6+B).

3. ## math

if cos(B-C)+cos(C-A)+cos(A-B)=-3/2 then prove that cosA+cosB+cosC=O and sinA+sinB+sinC=O after that prove that cos(B-C)=cos(C-A)=cos(A-B)=-1/2

4. ## maths

If sinA=1/2 then find cos^3A-3cosA.

5. ## Math

prove that sinA/(1+cosA) + (1+cosA)/(sinA) = 2cosecA

6. ## Pre-calculus (Trigonometry)

The rotating spotlight from the Coast Guard ship can illuminate up to a distance of 250 m. An observer on the shore is 500 m from the ship. HIs line of sight to the ship makes an angle of 20 degrees with the shoreline. What length of shoreline is

7. ## math (trigonometry)

if tan A/2 =cosecA-sin A then prove cos^2 A/2=cos 36 degree

8. ## maths

sinA+cosA=p and secA+CosecA=q then show that q[p^2-1]=2p

9. ## Maths, Divine International Public School

If 15Cot=8, find (1+SinA)(1-SinA)/(1+CosA)(1-CosA)

10. ## math

Prove that sinA+sinB+sinC=-4cosA/2cosB/2cosC/2

11. ## maths

If cosA + sinA= root2 cosA Show that cosA - sinA= root2 sinA

12. ## Maths

Cos^2A/sinA-cosecA+sinA=0 Prove lHS =RHS

13. ## further mathematics

Let P=(cosA sinA) (sinA cosA) Q=(cosB sinA) (sinB cosA) show that PQ=(cosA(A-B) sin(A B)) (sinA(A B) cos(A-B))

14. ## Trigonometry

Prove that sin3A+sin2A-sinA = 4sinAcosA/2cos3A/2

15. ## Maths

Given that sinA=2/5 and that A is obtuse,find the value of cosA. 👍 0 👎 0 👁 25 asked by Raj yesterday at 4:18am sinA = 2/5, so cosA = √21/5 But A is in QII, so cosA = -√21/5 👍 0 👎 0 posted by oobleck yesterday at 6:51am Why not

16. ## precalculus

Given sina= 3/4 and cosB = (-5)/13 and this is Quad II find cos(a+B)

17. ## Math

Hello I am having trouble with proving this: sinA/secA+secA/cscA = tan(A)(2-sin^2(A)) So far I've gotten SinA/(1/cosA) + (1/cosA)/(1/sinA) SinACosA + sinA/cosA I am stuck here, not even sure if multiplying by the reciprocal was the right step..

18. ## math

how do you solve this.prove: cos2A plus cosA divided by sin2A minus sinA equal to cos2A plus 1 divided by sinA

19. ## Math

A 5.0m ladder is leaning 3.1m up the wall. What is the angle the ladder makes with the ground? Would this be..... sinA=3.1/5.0 sinA=0.62 sin^-1=38degrees?

20. ## maths (trigonometry)

please solve these if possible Q1. If sinx +siny=3(cosy-cosx) then the value of sin3x/sin3y. Q2. If sina ,cosa,and tan a are in g.p.then cos cubea+cos square a is equal to

21. ## Trig

prove that tanA divided by the sinA equals the secA

22. ## Maths

TanA=√2-1 then find secA.sinA+tan^2A-cosecA

23. ## trig

if 5cos A plus 3=0 and 180

24. ## maths

If a cosA - b sinA = c . Prove that a sinA + b cosA = _+√a^2 + b^2 - c^2

25. ## trig

If (cosa-sina)/sina = 2 , then what is tga = ?

26. ## precal desperate

Given sina= 3/4 and cosB = (-5)/13 and this is Quad II find cos(a+B)

27. ## math

12. IF 1/SinA+1/CosA=1/SinB+1/CosB ,PROVE THAT: Cot{(A+B)/2}=TanA.TanB

28. ## Math

If 1/sinA+1/cosA =1/sinB+1/cosB, prove that: cot(A/2+B/2) = TanA. TanB

29. ## Maths

Prove That Sin2A+SIN2B+SIN2C/SINA+SINB+SINC=8SinA/2SINB/2SINC/2

30. ## Maths

If sina+7sinb=4 (sinc+2sind) and cosa+7cosb=4 (cosc+2cosd), how do I prove that 2cos(a-d) =7cos(b-c)?

31. ## maths Pls help trig

1 .If tanA=1/3 and tanB=1/7 (both A and B are acute),calculate 50sin(2A +B) 2.1Prove that sin2A+2cosA-2cos^3A/1+sinA =sin2A 2.2 for which values of A in the interval[-360;360] is the identity in 2.1 undefined? 3.If tanB=3/4 , 0

32. ## math

sinA+cosA=p ,secA+cosecA=q (cosA)^2/[2-2(sinA)^2-(cosecA)^2]=p^2/(2(p^2)-q^2

33. ## Trigonometry

IfA=340°, prove that 2sinA/2 = -(v1+sinA) + (v1-sinA)

34. ## Maths

Prove: 1+(TanA/SinB)^2/1+(TanA/SinC)^2 = 1+(SinA/TanB)^2/1+(SinA/TanC)^2

35. ## Math, Inequalities

Prove the following inequalities. Then state for which values the LHS equals RHS. 1) a^2 + b^2 ≥ 2(a-b-1) 2) Given a + b = 1, prove the inequality a^2 + b^2 ≥ 1/2 Please explain how you solved it. Thanks.

36. ## Math

A=5 sec(A)/1-4sinA.sinA +cosecA/4cosA.cosA-1 find value

37. ## trigonometry

Prove : 1 + Sin2A/ Cos2A = CosA + SinA / CosA- SinA

38. ## trig

I need to count this: a) 1-tg^2a/1+ctg^2a, when sina =2/3 b) 1-tg^2a/1-ctg^2a, when cosa= -1/3 c) tga * cos^2a, when sina + cosa=5/7 d) tg^2a + 1/sina * 1/cosa + ctg^2a, when tga + ctga =5

39. ## maths

prove that secA(1-sinA)-2tanA=1

40. ## maths

if 13 cos a=12, find the the value of sec a+sina?

41. ## trig

how do you do sinAcosA=cosA-cos^3A/sinA

42. ## maths trignometry

Prove that. √seca+2sina/seca-2sina=Sina+cosa/sina-cosa

43. ## 11

SinA + sinB/sinA - sinB= tanA+B/2cotA-B/2

44. ## Maths

(x squared +y squared +z squared) / 3 = (x/3+y/3+z/3) squared Prove that if LHS equals to RHS, then all x=y=z Thank you

45. ## math

If sina+7sinb=4 (sinc+2sind) and cosa+7cosb=4 (cosc+2cosd), how do I prove that 2cos(a-d) =7cos(b-c)?

46. ## trig

Please help me how to do this: 1) 1 + sina*cosa / (cosa + sina)^2 = 2) sina + cosa / 1- 2sin^2a =

47. ## Trig

Please help with this one. I've worked it out in so many ways and can't tell what's correct. sinA sinA ----- - ------ 1+sinA 1-sinA Which answer is correct for the problem above? a) 1+cotA b) sinA tanA c) -2tan^2A d) secA cscA common denominator: 1-sin^2 A

48. ## Maths

Hi, can someone give me the answer to this question: secA-tanA=1/4. Find cosA I got: CosA=4(1-sinA) Is my answer good? Now multply each side by (1+sinA) CosA(1+sinA)=4 cos^2 A CosA=1/4 (1+sinA) 16(1-sinA)=1+sinA 15=17SinA So you have sinA, now find Cos A

49. ## mathematics trignometry

prove that the following are identity 1. (cotA+cosecA-1)/(cotA-cosecA+1)=cosecA+cotA 2. (sinA-cosA+1)/(sinA+cosA-1)= 1/(secA-tanA)

50. ## trig

prove that :cosA-sinA+1/cosA+sinA-1=cosecA+cotA

51. ## Trigonometric Identities

Verify/prove the following: (sinA+tanA)/(1+secA) = sinA ______________________________ tanu = 1+sinu-cos^2u/cosu(1+sinu) __________________________________ cotu = (2+cscu/secu)-2cosu ______________________________ tanAsinA/tanA+sinA = tanA-sinA/tanAsinA

52. ## Math

In any angle ABC prove that the perimeter = a/Sin A(Sin A + Sin B + Sin C) Start with perimeter = a+b+c but b= aSinB/sinA and c= aSinC/SinA and if you don't remember, a=a=a*SinA/ SinA

53. ## MathS triG

1 .If tanA=1/3 and tanB=1/7 (both A and B are acute),calculate 50sin(2A +B) 2.1Prove that sin2A+2cosA-2cos^3A/1+sinA =sin2A 2.2 for which values of A in the interval[-360;360] is the identity in 2.1 undefined? 3.If tanB=3/4 , 0

54. ## math

if tanA=root2-1, prove that (secA.sinA tan squareA-cosecA) =(12-¡Ì5)/2

55. ## trigonometry

x×sin^3A=y , cos^3A = sinA × cosA , x×sinA= y×cosA , then prove that x^2+ y^2= 1 I have no idea

56. ## math

sinA+cosA=p ,secA+cosecA=q (cosA)^2/[2-2(sinA)^2-(cosecA)^2]=p^2/(2(p^2)-q^2

57. ## Maths

Prove that [sinA/(1-cosA)-(1-cosA)/sinA]*[cosA/(1+sinA)+(1+sinA)/cosA]=4cosecA I the second part as 2 secA

58. ## Trig

IfA=340°, prove that 2cosA/2 = -(v1+sinA) - (v1-sinA)

59. ## math

find all solutions in the interval [0,2 pi) sin(x+(3.14/3) + sin(x- 3.14/3) =1 sin^4 x cos^2 x Since sin (a+b) = sina cosb + cosb sina and sin (a-b) = sina cosb - cosb sina, the first problem can be written 2 sin x cos (pi/3)= sin x The solution to sin x =

60. ## algebra

i have a problem in dis sum from complex numbers prove that (1+sinA+icosA)/(1-sinA-icosA)=i(secA+tanA)

61. ## Math

CosA/1+sinA=1-sinA/cosA I have to prove the identity each side has to b the same how would i do that? I have a unit test on monday so im doing practice questions

62. ## Algebra

I'm not quite sure about these problems. I know how to do them, but it seems that I get the wrong answer. Maybe I'm supposed to get 'no solution' but I'm not sure. Could someone please help me with them? 5|6-5x|=15x-35 2|3x-7|=10x-8 1/4|4x+7|=8x+16 Ok for

63. ## Pre-Calculus

How can the following two identities be verified? 1. (cos^2y)/(1-siny)=1+siny 2. sin^2a-sin^4a=cos^2a-cos^4a Thanks! change cos^2a to 1-sin^2a=(1-sina)(1+sina) Thank you. I figured out the first one with your help, but I'm still stuck on the second. Any

64. ## Math

If secB=x,tanB=y(cosecA-cotA)=4/3,sinA+cosA=?

65. ## Maths

Test the solution of an equation: Prove that x=5 is a solution of the equation: 3x-3=2x+2 LHS= RHS= LHS=RHS,ie x=5 is the solution.

66. ## mathematics trignometry

if tanA=ntanX sinA=msinX then prove that cos^2A=(m^2-1)/(n^2-1)

67. ## maths(trigonometry)

prove that sinA-cosA+1/sinA+cosA-1=1/secA-tanA

68. ## math (trig)

i have some problems doing trig the first one is: Show that cos(x/2) sin(3x/2) = ½(sinx + sin2x) i know that you are supposed to substitute all those trig function things in it but i kind of forgot how to the only that i can see substituting in is the

69. ## trig

determine wheather each of the following is an identity or not prove it 1. cos^2a+sec^2a=2+sina 2. cot^2a+cosa=sin^2a

70. ## Trig - Ambiguous Cases

Triangle HAV has

71. ## math

Determine exact value of cos(cos^-1(19 pi)). is this the cos (a+b)= cos a cos b- sina sin b? or is it something different. When plugging it in the calculator, do we enter it with cos and then the (cos^-1(19 pi)).

72. ## Math - Vectors

If "u = (2,2,-1)", "v = (3,-1,0)" and "w = (1,7,8)", verify that "u (dot) (v + w) = u (dot) v + u (dot) w". My work: LHS: u (dot) (v + w) = (2,2,-1) (dot) (4,6,8) = [(2,2,-1) (dot) (3,-1,0)] + [(2,2,-1) (dot) (1,7,8)] = [u (dot) v] + [u (dot) w] Therefore,

73. ## trig

Solve (1+tan square A)(1-sinA)(1+ sinA)

74. ## Maths trigonometry

Prove that cosec A_cotA by cosecA+Costa + cosecA+ Cot A by cosecA_cotA=2 cosec squareA_1=2Ã—1+cos squares by1_cos squareA

75. ## trig

Prove : (sinA-cosA+1)/(sinA+cosA-1) = (1+sinA)/cosA

76. ## math

prove that 1-tan 4 A by1+tan 4 A =cosA + sinA by cosA - sinA

77. ## trig

Prove: 1/cos2A+sin2A/cos2A=sinA+cosA/cosA-sinA

78. ## trig

Prove: 1/cos2A+sin2A/cos2A=sinA+cosA/cosA-sinA

79. ## trig

How to do this one? (sina/1-cosa) + (1-cosa/sina) = Also, wanted to ask if I did another one right: 1 - sin^2a + tg^2a * cos^2a = 1 - sin^2a + (sina/cosa)^2 * cos^2a = 1 - sin^2a + sin^2a = 1 ???

80. ## trig

Prove that sin(A+B+C+)cos(B+C)-cos(A+B+C)sin(B+C)=sinA

81. ## Math: Law of Vectors (Cross Product)

(au) × v + (bu) × v = [(a + b)u] × v u = ( x , y , z ) v = ( x₂, y₂,z₂) LHS: = (au) × v + (bu) × v = [ ay z₂- y₂az , - (axz₂- x₂az) , axy₂- x₂ay ] + [ by z₂- y₂bz , - (bxz₂- x₂bz) , bxy₂- x₂by ] RHS: = [(a + b)u] × v = [

82. ## trig

Establish the following identity: CosA/1-TanA + SinA/1-CotA = CosA-SinA

83. ## Trig

I don't know the physics behind Snell's Law, but I can do the math Snell's Law says sin(angle of incidence)/sin(angle of reflection) = refractive index since you know the two angles... sin45/sin27 = refractive index =1.5575365 so for an angle of refection

84. ## algebra

prove that cosA/1-sinA=2cosecA

85. ## Math trigonometry

Prove sinA/1+cosA =tan1/2A

86. ## mathamethics

RHS and LHS . 5p + 3 = 2p + 9

87. ## mathamethics

RHS and LHS . 5p + 3 = 2p + 9

88. ## math

if A+B+C=180degrees, prove that 2sin(B+C)sinA=1-cos2A

verify that cos(90+A)=-sinA is an identity.

90. ## Trigonometric Identities

Verify/prove that: sinAcosA/1-cosA = sin^2/tanA-sinA

91. ## Math

Find angle A if it is greater than or equal to 0 degrees and smaller than or equal to 180 degrees. round to the nearest tenth of a degree, if necessary. a) sinA = 0.5 b) cosA = -0.5 e) cosA = 0.4561 g) sinA = 0.5736 PLEASE HELP WID THIS!!:( i tried so

93. ## TRIG!

Posted by hayden on Monday, February 23, 2009 at 4:05pm. sin^6 x + cos^6 x=1 - (3/4)sin^2 2x work on one side only! Responses Trig please help! - Reiny, Monday, February 23, 2009 at 4:27pm LS looks like the sum of cubes sin^6 x + cos^6 x = (sin^2x)^3 +

94. ## trig

I need to prove equality. a) (sina + cosa)^2 -1 / ctga - sinacosa = 2tg^2a b) (sin^2x/sinx-cosx) - (sinx+cosx/tg^2x+1) = sinx + cosx c) sin^4a - sin^2a - cos^4a + cos^2a = cosπ/2 How to do these?

95. ## math

Given that [sin(A-B)/cos(A+B)]=1/3[tan(A-B)], find the values of cosB if sinA=1/2

97. ## math

SinA➖cosA/sinA➕cosA➕sinA➕cosA/sinA➖cosA=-2/cos2A

98. ## Trigonomentry plz help

tanA=ntanB sinA=msinB find cos^2A in terms of 'm' and 'n' plz help

99. ## trigonometry

sinA= 3/5 and C=17 Finding a and b Their two triangles and i have to find the ratio i just can’t seem to set up the problem right but i gave an example of one of the practice exercise that dealt with finding only (a) so i got confused with finding a and

100. ## Algebra II/ Trig

Should the triangle be solved beginning with Laws of Sines or Laws of Cosines. Then solve the triangle and round to the nearest tenth. a=16, b=13, c=10 I got this answer but it is wrong and don't understand where I made the mistake. a=16, b=13, c=10