Integral problem

[BobbyJones]

I wasent to sure on this question

"Integral sign" 20(3x+1)^19 dx


Can someone do this step by step becuase I get confused with the dx at the end.

 

[renegade05]

I wasent to sure on this question

"Integral sign" 20(3x+1)^19 dx


Can someone do this step by step becuase I get confused with the dx at the end.

No one will do this for you step by step on this forum. You must show us where you are stuck. Why are you confused about the dx at the end? Do you know what the integral sign means?

The key to understanding this is to understand how riemann sums work. The dx is analogous to the number of sub-intervals as they go to infinity.

 

[BobbyJones]

Is this right so far:

"Integral sign" 20(3x+1)^19 dx


"Integral sign" 20(u)^19 du/3 u= 3x+1 du/dx = 3 therefore dx =du/3


1/3 u^20 + C

1/3 (3x+1)^20 + C

Is this correct

 

[srmichael]

Is this right so far:

"Integral sign" 20(3x+1)^19 dx


"Integral sign" 20(u)^19 du/3 u= 3x+1 du/dx = 3 therefore dx =du/3


1/3 u^20 + C

1/3 (3x+1)^20 + C

Is this correct

Yup!