Question

If sec = 5/4 show that (sin - 2cos ) (tan - cot) = 12/7

Answer 1

Answer:

proved

Step-by-step explanation:

sec = 5/4

cos = 4/5

sin = √(1-4²/5²)

    = √(9/25) = 3/5

tan = sin / cos

      = (3/5)/(4/5) = 3/4

cot = 4/3

LHS

(sin - 2cos )/ (tan - cot)

= (3/5 - 2*4/5)/(3/4 - 4/3)

=  (-1)/(-7/12)

= 12/7

RHS