Let $f(x) = 4x - 7$, $g(x) = (x + 1)^2$, and $s(x) = f(x) + g(x)$. What is $s(3)$?
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Let $f(x) = 2x^2 + 3x - 9,$ $g(x) = 5x + 11,$ and $h(x) = -3x^2 + 1.$ Find $f(x) - g(x) + h(x).$
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Let $f(x) = 3x + 2$ and $g(x) = x^2 - 5x - 1.$ Find $f(g(x)).$
thanks
+128460 First one
g(x) = (x + 1)^2 = x^2 + 2x + 1
f(x) = 4x - 7
f(x) + g(x) = x^2 + 6x - 6 = s(x)
s(3) = (3)^2 + 6(3) - 6 = 21
Second one
f(x) - g(x) = ( 2x^2 + 3x - 9) - ( 5x + 11) = 2x^2 - 2x - 20
f(x) - g(x) + h(x) = (2x^2 - 2x - 20) + ( -3x^2 + 1) = -x^2 -2x -19
Last one
f(g) means that we are putting g into f....so we have
3 ( x^2 -5x -1 ) + 2 =
3x^2 - 15x - 3 + 2
3x^2 - 15x - 1
