Test B review, no calculators please help

Question

Answer 1

16)

Given function is

Apply derivative both sides with respect to x.

Substitute x = 3

Solution : Option (e) is the Correct Choice.

Answer 2

17)

x(t) = t² - 7t + 12

Instantaneous rate of change of x(t) is x'(t).

Apply derivative both sides with respect to x.

(d/dx)x(t) = (d/dx) ( t² - 7t + 12 )

x'(t) = 2t - 7

Instantaneous rate of change of x(t) is equals to zero.

x'(t) = 0   ⇒   2t - 7 = 0   ⇒   2t = 7  ⇒  t = 7/2

t = 3.5

Solution : Option (c) is the Correct Choice.

Answer 3

19)

Given matrix

Solution : Option (d) is the Correct Choice.