Question

A+B+C =90 DEGREES then cos 2a+cos2b-cos2c​

Answer 1

Answer:

take a=30°

take b=30°

take c=30°

-1-4 Cos A Cos B Cos C

Answer 2

Given a+b+c=90 degrees

let a = 30°, b=30° and c=30°

Now; cos 2(30)+ cos 2(30)- cos 2(30)

=cos 60+ cos 60- cos 60

=cos 60°

=1/2

Hope this helps you...

Mark it as brainliest..and don't forget to rate it..