Shifting Functions Math Example 4

Follow the full solution, then compare it with the other examples linked below.

Example 4

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Write the equation of the function whose graph is y=xy=\sqrt{x} shifted right 99 and reflected over the xx-axis. State the domain.

Solution

  1. 1
    Shift right 99: xโˆ’9\sqrt{x-9}. Reflect over xx-axis (multiply by โˆ’1-1): โˆ’xโˆ’9-\sqrt{x-9}.
  2. 2
    Domain: xโˆ’9โ‰ฅ0โ‡’xโ‰ฅ9x-9\geq0 \Rightarrow x\geq9. Domain =[9,โˆž)=[9,\infty).

Answer

y=โˆ’xโˆ’9y=-\sqrt{x-9}; domain [9,โˆž)[9,\infty)
Combining a shift with a reflection: first shift the argument (xโ†’xโˆ’9x\to x-9), then apply the vertical reflection (multiply by โˆ’1-1). The domain shifts with the function โ€” the square root requires its argument to be non-negative.

About Shifting Functions

Shifting a function translates its graph horizontally or vertically without changing its shape: f(xโˆ’h)+kf(x - h) + k shifts right by hh and up by kk.

Learn more about Shifting Functions โ†’

More Shifting Functions Examples