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Another Exponential Question (1 Viewer)

jaychouf4n

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How do i find the primitive for the function

(6x^2-8x+6)e^(x^3-2x^2+3x-5)

i.e. 13C 8 a)

and can you please explain the reasoning :):)
 

foram

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jaychouf4n said:
How do i find the primitive for the function

(6x^2-8x+6)e^(x^3-2x^2+3x-5)

i.e. 13C 8 a)

and can you please explain the reasoning :):)
Let f(x) = x^3-2x^2+3x-5

Notice that (6x^2-8x+6) = 2 f'(x)

Therefore the question is in the form 2.f'(x).e^(f(x)

Therefore the primitive function is

2e^f(x)
=2e^(x^3-2x^2+3x-5)
 

jaychouf4n

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Thanks!!

Another question

sorry XD

diffrentiate e^x+e^-x

That's e^x-e^-x

so how do i use this to find the definite integral of (e^x-e^-x)/(e^x+e^-x)
 

foram

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jaychouf4n said:
Thanks!!

Another question

sorry XD

diffrentiate e^x+e^-x

That's e^x-e^-x

so how do i use this to find the definite integral of (e^x-e^-x)/(e^x+e^-x)
f(x)=e^x+e^-x
f'(x)=e^x-e^-x

(e^x-e^-x)/(e^x+e^-x)= f'(x)/f(x)

Integral of f'(x)/f(x) = ln[f(x)]
ln(e^x+e^-x)+C
 

jaychouf4n

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ARGH

another question xD

how do i use a=e^log a to find the primitive of

a^x+ax
 

foram

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jaychouf4n said:
ARGH

another question xD

how do i use a=e^log a to find the primitive of

a^x+ax
a^x = e^xlna

Integral of a^x+ax = (e^xlna)/lna + (ax^2)/2 + C
=(a^x)/lna + (ax^2)/2 +C
 

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