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indefinite integral (1 Viewer)

Mr Chi

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( 4x^3+3x^2+5/x^2 dx
)
I cant get these sought of ones can someone please help?
 

insert-username

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You need to write out the individual parts of the fraction, cancel common factors, and then write in terms of negative indices if necessary:

(
) (4x3 + 3x2 + 5)/x2 dx

=
(
) (4x3)/x2 + (3x2)/x2 + 5/x2 dx

=
(
)(4x + 3 + 5x-2) dx

= 2x2 + 3x - 5x-1


I_F
 
Last edited:
P

pLuvia

Guest
∫ [4x3+3x2+5/x2] dx
Is this what you mean?

If so
∫ [4x3+3x2+5/x2] dx
= x4+x3-5/x + C

If it's ∫ [4x3+3x2+5]/[x2] dx
= ∫ [4x3/x2+3x2/x2+5/x2] dx
= ∫ [4x + 3 + 5x-2]dx
= 2x2 + 3x - 5x-1 +C
= 2x2 + 3x - 5/x +C

P.S insert-username you forgot to add C the constant
 

insert-username

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Damn. Damn Damn Damn Damn Damn. I always forget the bloody constant! :p


I_F
 

insert-username

Wandering the Lacuna
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I was doing some integration today, and I kept leaving it out! So friggin' annoying! Automatic one mark off! :p


I_F
 
P

pLuvia

Guest
lol, just keep practicing :p, just make a note before you do those questions in a test :) usually works if you remember to write it down
 

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