Answer:
sin2θ = -24/25
cos2θ = 7/25
tan2θ = -24/7
Step-by-step explanation:
sinθ = 3/5
θ is in Quadrant II. So 2θ is in Quadrant III or IV. So sin2θ is negative. Nothing can be said about cos and tan yet.
sin135 = 0.707 > 3/5.
So θ > 135.
2θ lies in Quadrant IV. So cos2θ is positive and tan2θ is negative.
cosθ = √(1 - sin²θ)
= -4/5
sin2θ = 2sinθcosθ = 2x(3/5)x(-4/5) = -24/25
cos2θ = 1 - 2sin²θ = 1 - 2x(3/5)² = 7/25
tan2θ = sin2θ/cos2θ = -24/7
