The given expression, 81a^6 - 100, is a difference of two squares. The first term 81a^6 is a square of 9a³. The second term, 100, is a square of 10. The factors of the given expression is therefore, (9a³ - 10) x (9a³ + 10).
Step-by-step explanation:
L.H.S
tanA * cosecA
=sinA/cosA * 1/sinA
now cancel sinA and sinA
then,
1/cosA
= secA
= RHS
hence proved
