Question

Help me to solve this fast ( prove it)

Answer 1

Explanation:

sec⁴A + tan⁴A = 1 + (2tan²A/cos²A)

LHS = sec⁴A + tan⁴A

= (sec²A)² + (tan²A)² {using formula of a²+b²)

= (sec²A-tan²A) + 2tan²A.sec²A

= 1 + {2tan²A.(1/cos²A)}

= 1 + (2tan²A/cos²A)