Question

Find tan theta equal to 2 find the value of cos 2 theta​

Answer 1

Explanation:

Given, tan theta =2

Find, cos ^2 theta

We have the equation ;

tan^2 +1 = sec^2

i. e., tan ^2 +1 =1/cos^2

(2)^2 +1=1/cos ^2

4+1=1/cos ^2

5=1/ cos ^2

cos^2=1/5

Hope it helps!