Question

Prove that root under 1 - cos a by 1 + cos a is equal to sin a by 1 + cos a

Answer 1

√1- cos a

√1+ cos a

=√(1 -cos a)(1+ cos a)

√(1+ cos a )(1+cos a )

=√(1-cos^2 a)

√(1+cos a )(1+ cos a)

=√sin^2 a

√(1+ cos a)^2

=sin a

1+cos a