Find the inverse of: f(x) = (2x + 3)/(x - 4)

To find the inverse of a function, f-1(x):1) set f(x) as y: y =  (2x + 3)/(x - 4)2) swap x and y: x = (2y + 3)/(y -4)3) solve the new equation for y: x(y -4) = 2y + 3 = xy -4x2y - xy = -4x - 3y(2 - x) = -4x -3y = (-4x-3)/(2-x) = f-1(x)

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Answered by Sophie I. Maths tutor

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