How do you graph f(x) = 2sqrtxf(x)=2x?

1 Answer
Nov 10, 2017

See below

Explanation:

f(x) = 2sqrtxf(x)=2x

If we are confined to the real numbers, f(x)f(x) is only defined for positive values of xx and the value 00.

This is because the square root of a negative number is complex.

Hence, f(x)f(x) cannot be plotted on the real xy-xyplane for x<0x<0.

Also interesting in this area. When we plot f(x)f(x) we use the so called 'Principal Square Root' which is only the positive values of f(x)f(x) although:

sqrt([f(x)]^2) = +-2 sqrtx[f(x)]2=±2x

This ensures the mapping f(x) harr xf(x)x is one-to-one so that f(x)f(x) is a true function of xx.

The graph of f(x)f(x) is shown below.

graph{2sqrtx [-14.12, 14.36, -6.76, 7.48]}