Guest

I didn't understand how to do this problem... How do you solve it?

I didn't understand how to do this problem... How do you solve it?

Question Image
Grade:11

1 Answers

Arun
25750 Points
5 years ago

Explanation:

sec(θ+α)+sec(θα)=2sec(θ) can be written as

1cos(θ+α)+1cos(θα)=2cosθ

or cos(θ+α)+cos(θα)cos(θ+α)cos(θα)=2cos(θ)

or2×2cosθcosαcos(θ+α+θα)+cos(θ+αθ+α)=2cosθ

or 2cosθcosαcos2θ+cos2α=1cosθ

or 2cos2θcosα=cos2θ+cos2α

or 2cos2θcosα=2cos2θ1+2cos2α1

or 2cos2θ(cosα1)=2cos2α2

or cos2θ=cos2α1cosα1=cosα+1

or cos2θ=2cos2(α2)

and cosθ=2cos(α2)

Think You Can Provide A Better Answer ?

ASK QUESTION

Get your questions answered by the expert for free