Antiderivatives

tuansmart

New member
Joined
Nov 6, 2009
Messages
3
Evaluate the indefinite integral: 8/x^4 + 4/15x
I know 8/x^4=-(8/3)x^-3
I need help on 4/15x. I know 4/15x is 4(15x^-1). If I put in zero it will be undefined. I don't know how to solve 4/15x. Can somebody help me?
 
(8x4+415x) dx = 8x4 dx+415x1 dx\displaystyle \int\bigg(\frac{8}{x^{4}}+\frac{4}{15x}\bigg) \ dx \ = \ 8 \int x^{-4} \ dx+\frac{4}{15} \int x^{-1} \ dx

= 83x3+415lnx+C\displaystyle = \ -\frac{8}{3}x^{-3}+\frac{4}{15}ln|x|+C

Note: 4/15x = 4x15; 4/(15x) = 415x, Im assuming you wanted the latter.\displaystyle Note: \ 4/15x \ = \ \frac{4x}{15}; \ 4/(15x) \ = \ \frac{4}{15x}, \ I'm \ assuming \ you \ wanted \ the \ latter.

Whether for emphasis or needed, a common courtesy is to use grouping symbols to avoid any\displaystyle Whether \ for \ emphasis \ or \ needed, \ a \ common \ courtesy \ is \ to \ use \ grouping \ symbols \ to \ avoid \ any

 ambiguity.\displaystyle \ ambiguity.
 
Top