Intergration Query (1 Viewer)

[Lukybear]

This integration is killing me:

S 2x(4+x^2)dx = (4+x^2)2

but

S 2x(4+x^2) dx = S 8x + 2x^3 = 4x^2 + x^4/2

Any help explaining?

 

[shaon0]

This integration is killing me:

S 2x(4+x^2)dx = (4+x^2)2

but

S 2x(4+x^2) dx = S 8x + 2x^3 = 4x^2 + x^4/2

Any help explaining?

Top ones meant to be 1/2*(4+x^2)^2 i think that may alter the outcome.
I{1}=8+4x^2+x^4/2+C=4x^2+x^4/2+K
I{2}=4x^2+x^4/2+A
=>A=K ie A=8+C

 

[Trebla]

 

[Lukybear]

oo nice...