Posted by Lynn on Friday, March 23, 2012 at 9:46pm.
sin^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
Related Questions
Trig....... - I need to prove that the following is true. Thanks (2tanx /1-tan^x...
precal - cosx/secx+sinx/cscx=sec^2x-tan^2x
pre-calc - Solve: cos(2x-180) - sin(x-90)=0 my work: cos2xcos180 + sin2xsin180= ...
trig - express this in sinx (1/ cscx + cotx )+ (1/cscx- cotx) i got 2sinx is ...
precal - sin^2x-1=sec^2x-tan^2x
Math-Trig - 1. Create an algebraic expression for sin(arccosx-arcsin3x) 2. The ...
Math - help really needed - Prove each idenity. 1+1/tan^2x=1/sin^2x 1/cosx-cosx=...
Trigonometry. - ( tanx/1-cotx )+ (cotx/1-tanx)= (1+secxcscx) Good one! ...
Trigonometry - How do you verify the equation is an identity? Tan^2x-tan^2y=sec^...
Maths - Solve this equation fo rx in the interval 0<=x<=360 ...
For Further Reading
