6²+8²=c²
36+64=c²
c²=100
c=10
31.+ addition
32. - subtraction
is proved
<h3><u>
Solution:</u></h3>
Given that,
------- (1)
First we will simplify the LHS and then compare it with RHS
------ (2)

Substitute this in eqn (2)

On simplification we get,


Cancelling the common terms (sinx + cosx)

We know secant is inverse of cosine

Thus L.H.S = R.H.S
Hence proved