Solve (4d)*(-5d)

$$( 4 d ) \times ( - 5 d )$$

Evaluate

$$-20d^{2}$$

Solution Steps

Multiply d and d to get d^{2}.

$$4d^{2}\left(-5\right)$$

Multiply 4 and -5 to get -20.

$$-20d^{2}$$

Differentiate w.r.t. d

$$-40d$$

Steps Using Definition of a Derivative

Multiply d and d to get d^{2}.

$$\frac{\mathrm{d}}{\mathrm{d}d}(4d^{2}\left(-5\right))$$

Multiply 4 and -5 to get -20.

$$\frac{\mathrm{d}}{\mathrm{d}d}(-20d^{2})$$

The derivative of ax^{n} is nax^{n-1}.

$$2\left(-20\right)d^{2-1}$$

Multiply 2 times -20.

$$-40d^{2-1}$$

Subtract 1 from 2.

$$-40d^{1}$$

For any term t, t^{1}=t.

$$-40d$$