What is the Power Rule?

1 Answer
Sep 27, 2017

If we have #y=x^n#, then we have a power rule for both differentiating and integrating

Differentiation

We "multiply by the power and subtract one from the power" :

Thus;

# dy/dx = d/dx (x^n) = nx^(n-1) #

Integration

We "add one to the power, and divide by that new power"

Thus:

# int \ y \ dx = int \ x^n \ dx = x^(n+1)/(n+1) + c #

Examples:

# d/dx( x^2 ) = 2x^(2-1) = 2x #
# d/dx( 3x^4 ) = 3(4)x^(4-1) = 12 x^3 #

# int \ x^2 \ dx = x^(2+1)/(2+1) + c = x^3/3 + c#
# int \ 3x^4 \ dx = 3x^(4+1)/(4+1) + c = 3/5x^5 + c#