How do you find the derivative of x+sqrt(x)?

1 Answer
Mar 3, 2016

(x+sqrt(x))'=1+1/(2sqrt(x))

Explanation:

Recall the following:

1. color(red)("Sum Rule"): [f(x)+g(x)]'=f'(x)+g'(x)
2. color(blue)("Power Rule"): (x^n)'=color(orange)nx^(color(orange)n-1)

Finding the Derivative
1. Start by rewriting sqrt(x) as x^(1/2). Recall that x is x^1.

(x+sqrt(x))'

=(x^1+x^(1/2))'

2. Using the color(red)("sum rule"), determine the derivative of each term in the expression. To do that, use the color(blue)("power rule").

=color(orange)1x^(color(orange)1-1)+color(orange)(1/2)x^(color(orange)(1/2)-1)

3. Simplify.

=color(orange)1x^0+color(orange)(1/2)x^(-1/2)

=color(orange)1(1)+color(orange)(1/2)(1/x)^(1/2)

=1+color(orange)(1/2)(1/sqrt(x))

color(green)(=1+1/(2sqrt(x)))

:., the derivative is 1+1/(2sqrt(x)).