Question

prove this.............​

Answer 1

Step-by-step explanation:

we have, 1+(tan alpha)(tan beta) = cos(alpha+beta)/(cos alpha)(cos beta)

let alpha = x

beta = y

so, LHS,,

1+tanxtany

= 1+sinx/cosx×siny/cosy

= (cosxcosy+sinxsiny)/cosxcosy

= cos(x-y)/cosxcosy =RHS

hence proved....

Answer 2

Answer:

Step-by-step explanation:mark me i needed

The answer is here,

Given that,

= > \: \frac{a + ib}{c + id} = p + iq

We can replace the " i " as " -i ".

= > \frac{a - ib}{c - id} = p - iq