Question

SOMEBODY HELP ME WITH THESE PLEASE! I really need the help like NOW PLS!

Answer 1

93. $g(n) = n - 4$
$f(n) = 2n^2 - 5n$

then $g(n) +f(n) = (n-4) + (2n^2 - 5n)$
                                $= n - 4 + 2n^2 - 5n$
                                $= 2n^2 -5n + n - 4$
                                $= 2n^2 - 4n -4$


95. $f(n) = -n+3$
      $g(n) = n^3 + 3n$
Then $f(n) . g(n) = (-n+3) . (n^3 + 3n)$
                                 $= -n^4 + 3n^3 - 3n^2 + 9n$
 

97. $f(x) = 3x+1$
$g(x) = 2x$
For finding f(g(x)) we will plugin value of g(x) in place of x in f(x).
$f(g(x)) = 3*(2x) + 1$
                  $= 6x + 1$


99. $f(n) = n - 3$
$g(n) = 2n^2 - 3n$

$g(-7) = 2*(-7)^2 - 3 * (-7) = 2* 49 + 21 = 98 + 21 = 119$
$f(g(-7)) = 119 - 3 = 116$