Q. Find the inverse of the functionf(x)=3x2−27,x≥0
Replace with y: To find the inverse of the function f(x)=3x2−27, we first replace f(x) with y to make the equation easier to work with.y=3x2−27
Swap x and y: Next, we swap x and y to begin solving for the new y, which will be the inverse function.x=3y2−27
Isolate y term: Now, we isolate the term containing y on one side by adding 27 to both sides of the equation.x+27=3y2
Divide by 3: We then divide both sides by 3 to solve for y2.(x+27)/3=y2
Take square root: Since we are looking for y and not y2, we take the square root of both sides. Remember that since x≥0, we only consider the positive square root because the original function is defined for x≥0.y=(x+27)/3
Rewrite inverse function: Finally, we rewrite the inverse function with the original function notation, replacing y with f−1(x).f−1(x)=3x+27
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