Question

Find derivative from first principle:
x² tanx​

Answer 1

f'(x) = 2.x.tan(x) + x²/cos²(x)

Explanation:

f(x) = x².tan(x)

=> f'(x) = (x²)' . tan(x) + x². (tan(x))'

= 2x.tan(x) + x² . 1/cos²(x)

=> f'(x) = 2.x.tan(x) + x²/cos²(x)