If  $y={{x}^{2}}-\tfrac{1}{x},$find $\tfrac{dy}{dx}$

Find the derivative of $\frac{\sin \theta }{\cos \theta }$

The derivative of $(2x+1)(3x+1)$ is

At what value of x does the function $y=3-2x+{{x}^{2}}$ minimum?

If $y=x\sin x,\text{ find }\tfrac{dy}{dx}$

If $y={{(2x+1)}^{3}},\text{ find }\frac{dy}{dx}$

The distance travelled by a particle from a fixed point is given as $s={{t}^{3}}-{{t}^{2}}-t+5$find the minimum distance that the particle can cover from the fixed point.

What is the value of x will make the function $x(4-x)$ a maximum?

If $s=(2+3t)(5t-4),\text{ find }\frac{ds}{dt}$ when t = $\tfrac{4}{5}$secs.

If $y=3\cos 4x,\text{ }\frac{dy}{dx}$ equals