Step by step Explanation :
Given : π < 2θ < 3π/2
We have to find the value of
We know that
cos2θ=2cos²θ-1
Then , cos4θ=2(cos2θ)²-1
➝ 1+cos4θ=2(cos2θ)²
Now ,
Here,
Now we will see that what θ mean here to us . As given in the equation
π < 2θ < 3π/2
It signifies that 2θ lies in the third Quadrant i.e 180° < 2θ < 270°
We know that : In third Quadrant cosine is -ve .
Now,
Now we'll find about θ
180° < 2θ < 270°
➝ 90° < θ < 135°
Thus , θ lies in second quadrant , where sin function is +ve .
Therefore, Correct option d)2sinθ
Copyright © 2024 EHUB.TIPS team's - All rights reserved.
Answers & Comments
Verified answer
Solution :
Step by step Explanation :
Given : π < 2θ < 3π/2
We have to find the value of
We know that
cos2θ=2cos²θ-1
Then , cos4θ=2(cos2θ)²-1
➝ 1+cos4θ=2(cos2θ)²
Now ,
Here,
Now we will see that what θ mean here to us . As given in the equation
π < 2θ < 3π/2
It signifies that 2θ lies in the third Quadrant i.e 180° < 2θ < 270°
We know that : In third Quadrant cosine is -ve .
Now,
Now we'll find about θ
180° < 2θ < 270°
➝ 90° < θ < 135°
Thus , θ lies in second quadrant , where sin function is +ve .
Therefore, Correct option d)2sinθ
Some More Formula's :