Question

find dy/dx when,y= 4x^3+cos x - tan x​

Answer 1

the answer is in the image

Answer 2

Solution :

Given, y = 4x³ + cosx - tanx

We have to find dy/dx.

Formulas to be used :

→ d/dx (xⁿ) = nx^(n - 1)

→ d/dx (cosx) = -sinx

→ d/dx (tanx) = sec²x

Now,

→ dy/dx = d/dx(4x³ + cosx - tanx)

→ dy/dx = d/dx (4x³) + d/dx (cosx) + d/dx (-tanx)

→ dy/dx = 4 d/dx(x³) - sinx - sec²x

→ dy/dx = 4 × 3x² - sinx - sec²x

→ dy/dx = 12x² - sinx - sec²x (Ans.)