Use the given information about the angle θ to find the exact value of...

Question

a. sin 2θ

b. cos 2θ

c. tan 2θ

 

for 

 

cot θ = -7, 3pi/2 < θ < 2pi

Answer 1

inverse cot of -7 is -0.1419

theta is between 3pi/2 and 2pi, so it is 2pi-0.1419

a. sin2theta=7/25

b. cos2theta=24/25

c. tan2theta=7/24

 

Answer 2

θ = arccot(-7) = 351.869898° which is in quadrant IV as required

 

2θ = 703.739796° and the trig functions of this angle wil be the same as an angle 360° less, i.e.

2θ = 343.739796

 

You can look up the trig functions for this angle as easily as I can!