Get Answers to all your Questions

header-bg qa

If f and g are real functions defined by f (x) = x^2 + 7 and g (x) = 3x + 5, find each of the following
(a) f (3) + g (- 5)

(b) f(1/2) \times g(14)

(c) f (- 2) + g (- 1)

(d) f (t) - f (- 2)

(e) (f(t) - f(5))/ (t - 5), if \: \: t \neq 5

Answers (1)

Given data: f(x) = x^2 + 7 & g(x) = 3x + 5

  1. f(3) + g(-5) = [(3)^2 + 7] + [3(-5) + 5]

= 16 - 10

= 6

  1. f( 1/2 ) \times g(14) = [(1/2)^2 + 7] \times [3 \times 14 + 5]

= 29/4 \times 47

= 1363/4

  1. f(-2) + g(-1) = [(-2)^2 + 7] + [(-1) + 5]

= 11 + 2 = 13

  1. f(t) - f(-2) = (t^2 + 7) - [(-2)^2 + 7]

= t^2 - 4

  1. f(t) - f(5)/ t - 5, (t is not equal to 5) = (t^2 + 7) - (5^2 + 7)/ t - 5

                                    =( t^2 + 7 - 32)/t - 5

                                   = (t^2 - 25)/ (t - 5)

                                    =(t - 5) (t + 5)/(t - 5)

                                  = t + 5

Posted by

infoexpert21

View full answer