Sunday

December 21, 2014

December 21, 2014

Posted by **Lynn** on Friday, March 23, 2012 at 9:46pm.

- precal -
**Reiny**, Saturday, March 24, 2012 at 12:52amsin^2x /cosx = 1/cos^2 x - 1

multiply each side by cos^2 x

sin^2 x cosx = 1 - cos^2x

(1 - cos^2x)cosx = 1 - cos^2x

cosx - cos^3x - 1 + cos^2x = 0

cos^3x - cos^2x - cosx + 1 = 0

cos^2x(cosx - 1) -(cosx - 1) = 0

(cosx-1)(cos^2x-1) =0

(cosx-1)(cosx-1)(cosx+1) = 0

cosx = 1 or cosx = -1

x = 0, 2π or x = π

**Answer this Question**

**Related Questions**

Precal - Verify the identity: sin^(1/2)x*cosx - sin^(5/2)*cosx = cos^3x sq root ...

Trigonometry - Prove the following trigonometric identities. please give a ...

Precalculus/Trig - I can't seem to prove these trig identities and would really ...

Confused! Pre-Cal - Verify that each equation is an identity.. tan A= sec a/csca...

Calculus - Q: If y=sinx/(1+tanx), find value of x not greater than pi, ...

Trigonometry. - ( tanx/1-cotx )+ (cotx/1-tanx)= (1+secxcscx) Good one! ...

Math - Use the fundamental identities to simplify the expression. csc Q / sec Q ...

math - show that 1-sin x/cosx + cosx/1-sin x = 2 sec x

Pre-Cal - Use the fundamental identities to simplify the expression. csc Q / sec...

Math(Please help) - Use the fundamental identities to simplify the expression. ...