Question

prove that cos square A minus 1 into cot square A + 1 equal to -1​

Answer 1

The solution is given in the above attachment.

Answer 2

Answer:

(Cos²A - 1)(Cot²A + 1) = -1

Step-by-step explanation:

to be proved

(Cos²A - 1)(Cot²A + 1) = -1

LHS = (Cos²A - 1)(Cot²A + 1)

Using CotA = CosA/SinA

= (Cos²A - 1)(Cos²A/Sin²A + 1)

= (Cos²A - 1)(Cos²A + Sin²A)/Sin²A

using Cos²A + Sin²A =   1

= (Cos²A - 1)(1)/Sin²A

=  (Cos²A - 1)/Sin²A

=  ( - Sin²A )/Sin²A

= - 1

= RHS

QED

Proved

(Cos²A - 1)(Cot²A + 1) = -1