8. Prove that (1 + tanA – secA) x (1 + tanA + SecA) = 2 tanA​

1 thought on “8. Prove that (1 + tanA – secA) x (1 + tanA + SecA) = 2 tanA​”

1. Step-by-step explanation:

   Using (a+b)(a-b) = a² – b²

   LHS =

   (1 + tanA – secA) x (1 + tanA + SecA)

   = ( 1 + tanA)² – sec²A

   = 1 + tan²A + 2tanA – sec²A

   Also, sec²A = 1 + tan²A

   = 1 + tan²A + 2tanA – 1 – tan²A

   = 2tanA = RHS

   Hence, proved

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