tanθcos2θ=(2tanθcos2θ-tanθ/1-tan2θ)

tanθcos2θ=(2tanθcos2θ-tanθ/1-tan2θ)

prove that sin(45+x).sin(45-x)=1/2cos2x

If cosα=0.173 and cosβ= 0.432 with both angles’ terminal rays in Quadrant-I, find the values of cos(α+β)=? cos(α-β)=? Your answers should be accurate to 4 decimal places. please help...

If cosα=0.891 and cosβ=0.577 with both angles’ terminal rays in Quadrant-I, find the values of tan(α+β) Your answers should be accurate to 4 decimal places. please help, thanks!

I dont quite remember how to solve this, if anyone could help.

The question is cos -105. I know how to do the process for it but for some reason my answer doesn't have the right negatives. I am getting: √2 + (-√6) -------------- ...

I am doing sum and difference formulas with sin, cos, and tan. I am doing tan75 with the difference formula. So tan 120-45 I have all the things found I just don't know...

Determine the exact value of cos(Pi/24)???

How do I rewrite (tanθ+secθ)/cosθ in terms of sinθ? (fully simplified)

prove that tan6.tan42.tan66.tan78=1

solve the equation for the solutions over the interval [0 degrees, 360 degrees) 6sec2xtanx=12tanx I am unsure of where to begin.

cos(3theta)=-1 solve for exact solutions over the interval [0,360 degrees] I am having trouble finding a place to start.

Proving identities

Find the exact value algebraically of sin(105°)

cos(2θ) = 1/√2 (1 divided by square root 2) 90° ≤ θ ≤ 180°

Solve step by step to get the answer

sinxcos^4x+cos^6x=

Hi, this is my first time using this site. So I have been staring at this trigonometric equation for a long while and looking for what it asks for. For what I know, I think I have to use sum of...

Prove sin4x = 4 (sin x-2 sin^3 x)/secx I can't seem to solve this! Halp!!!

Solve the given equation over the interval [0,2): 2sinx+ (sqrt 3) sin^2x=-(sqrt 3) cos^2x A. x=0, and x=(pi/2), and x=(3 pi/2), and x=2(pi)x=(3 pi/2), and x=(7 pi/2) b. x=(4 pi/3) and...