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How do you prove the following identity sec x - cos x equals sin x tan x?
Wiki User
∙ 14y ago
you need this identities to solve the problem..that is something you have to memorized sec x= 1/cosx 1-cos2x= sin2x tanx= sin x/cosx also, sin 2x= (sinx)(sinx) sec x - cosx= sin x tanx (1/cosx)-cosx= sin x tanx .. 1-cos2x / cosx=sin x tanx sin2x/ cosx= sin x tanx (sin x/cox)( sin x)= sin x tanx tanx sinx= sin x tanx
Wiki User
∙ 14y ago
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Prove identity cos 2xcot2 x-1cot2 x1?
the questions is 2x=(cot^2 x-1)/(cot^2 x+1)
What are the sum and difference identities for the sine cosine and tangent functions?
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1 over cos x equals what?
sec(x)=1/cos(x), by definition of secant.
What is 7 x 60 x cos 60 equals?
cos(60) = 0.57 x 60 x cos(60) = 7 x 30 = 210
Prove that secB - cosB equals tanBsinB?
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How do you solve the following identity sec x - cos x equals sin x tan x?
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To show that (cos tan = sin) ??? Remember that tan = (sin/cos) When you substitute it for tan, cos tan = cos (sin/cos) = sin QED
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No, (sinx)^2 + (cosx)^2=1 is though
How do you solve trignometric identities?
tan(x) = sin(x)/cos(x) Therefore, all trigonometric ratios can be expressed in terms of sin and cos. So the identity can be rewritten in terms of sin and cos. Then there are only two "tools": sin^2(x) + cos^2(x) = 1 and sin(x) = cos(pi/2 - x) Suitable use of these will enable you to prove the identity.
Is cos 2 x sec x equals 2 cos x - sec x an identity?
Yes, it is. the basic identity is for a double angle relation: cos 2x = 2 cosx cos x -1 since sec x =1/cos x if we multiply both sides by sec x we get cos2xsec x = 2cosxcos x/cos x -1/cos x = 2cos x - sec x
Prove identity cos 2xcot2 x-1cot2 x1?
the questions is 2x=(cot^2 x-1)/(cot^2 x+1)
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sin(3A) = sin(2A + A) = sin(2A)*cos(A) + cos(2A)*sin(A)= sin(A+A)*cos(A) + cos(A+A)*sin(A) = 2*sin(A)*cos(A)*cos(A) + {cos^2(A) - sin^2(A)}*sin(A) = 2*sin(A)*cos^2(A) + sin(a)*cos^2(A) - sin^3(A) = 3*sin(A)*cos^2(A) - sin^3(A)
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Sorry, but cos(50)sin(40) - cos(40)sin(50) is -0.1736, which is not even close to sin(90) which is 1.This does not work in radians, either. Please restate your question.
Sec - cos equals tansin?
Prove that tan(x)sin(x) = sec(x)-cos(x) tan(x)sin(x) = [sin(x) / cos (x)] sin(x) = sin2(x) / cos(x) = [1-cos2(x)] / cos(x) = 1/cos(x) - cos2(x)/ cos(x) = sec(x)-cos(x) Q.E.D
What is the identity for tan theta?
The identity for tan(theta) is sin(theta)/cos(theta).
