Question

The functions u and w are defined as follows.

u(x) = 2x+2
w(x) = – 2x² +2
Find the value of w (u(2)).

Answer 1

w(u(2)) = -70

Explanation:

u(x) = 2x + 2

w(x) = -2
`x^(2)` + 2

w ( u (2) )

Find u(2), substitute in 2 for x in the function u.

u(2) = 2(2) + 2

= 4 + 2

= 6

w(u(2))

= w(6)

Now subsitute in 6 for x, in the function w.

w(6) = -2
`(6)^(2)` + 2

= -2 * 36 + 2

= -72 + 2

= -70

w(6) = -70

w(u(2)) = -70