Question

cos 2 a = 1-tan2 a by 1 + tan 2 a

Answer 1

Answer:

.S=

1+tan

2

A

1−tan

2

A

=

sec

2

A

1−tan

2

A

∵(1+tan

2

A=sec

2

A)

=cos

2

A−

sec

2

A

tan

2

A

=cos

2

A−sin

2

A

=cos

2

A−(1−cos

2

A)

=2cos

2

A−1

=R.H.S

Video Explanation

Solution to Question ID 728989