Question

Given the function: f(x) = 2x3 - 3/2x, find f(-4).

Answer 1

Answer:

D) -122

Step-by-step explanation:

Given:

$f(x) = 2x^3-\frac{3}2x$

We need to find f(-4).

Now by substituting the value of x =-4 in above equation we get;

$f(-4)= 2\times(-4)^3-\frac{3}{2}\times(-4)$

By using PEDMAS we will solve for exponential function first we get;

Now we know that $(-4)^3=-64$

So we get;

$f(-4)= 2\times(-64)-\frac{3}{2}\times(-4)$

Now using PEDMAS we will solve division.

$f(-4)= 2\times(-64)-1.5\times(-4)$

Now using PEDMAS we solve multiplication.

$f(-4)= -128+6$

Finally by subtraction we get;

$f(-4)= -122$