Question

Prove that:
[cos x + sin^2 x]/[cos^2 x - sin^2 x]
= 1 + cos x ​

Answer 1

Answer:

the answer

Explanation:

LHS :

(cosx+cosy)

2

+(sinx−siny)

2

=(cos

2

x+cos

2

y+2cosxcosy)+(sin

2

x+sin

2

y−2sinxsiny)

=(cos

2

x+sin

2

y)+(cos

2

x+sin

2

y)+2(cosxcosy−sinxsiny)

=1+1+2cos(x+y)

=2+2cos(x+y)

=2[1+cos(x+y)]

=4 cos

2

(

2

x+y

) = RHS