Question

The value of the polynomial 7x^4 + 3x^2 – 4, when x = – 2 is:​

Answer 1

Step-by-step explanation:

given polynomial:

y = 7x^4 + 3x^2 - 4

now, this (7x^4 + 3x^2 - 4) acts like a machine.

everytime i give my input as x the machine will evaluate according to the formula and give output as y.

so, we can say y varies according to input.

y varies according to x

y is a function of x.

y = f(x) = (7x^4 + 3x^2 - 4)

if i give my input as x= (-2) what will be y?

f(-2) = 7×(-2)^4 + 3×(-2)^2 -4

= 7 × 16 + 3 × 4 - 4

= 112 + 12 - 4

= 124 - 4

= 120.

so, value of polynomial is 120.