f(x) = 5 – x and g(x) = 3x + 7 (a) Simplify f(2x) + g(x – 1)

May look hard at first but once understood is simple.Question is asking to add two functions together.Firstly we begin by calculation f(2x) We know that f(x) = 5 – x, to find f(2x) we replace the x by 2xThis gives us f(2x) = 2 -2xNext we calculate g(x-1) this one is a little trickier but follows the same ideawe know that g(x) = 3x +7, to find g(x-1) we replace the x by (x-1)This gives us g(x-1) = 3(x-1) +7 We then expand the brackets to find g(x-1) = 3x-3 +7Therefore f(2x) + g(x-1) = 2-2x +3x-3+7= 9 + x

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Answered by Matthew B. Maths tutor

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