Year 12s: what will be the first way you research your future options? >>

Year 12s: what will be the first way you research your future options? >>

Year 12s: what will be the first way you research your future options? >>

C1 AQA Jan 08 integration help

integrate x cubed -7x-6 dx with x values 3 and -1

I was able to get x4/4 -7^2/2-6x

then put the values for x in and got 81/4 - 63/2 - 18- 1/4 - 7/2 +6
when I added them together I did not get the final answer of -32.
what did I do wrong

Original post by nocoolusername

integrate x cubed -7x-6 dx with x values 3 and -1

I was able to get x4/4 -7^2/2-6x

then put the values for x in and got 81/4 - 63/2 - 18- 1/4 - 7/2 +6
when I added them together I did not get the final answer of -32.
what did I do wrong

You did not use latex :smile:

:smile:

\displaystyle \int^3_{-1} x^3 - 7x - 6 dx = [\frac{x^4}{4} - \frac{7x^2}{2} - 6x]^3_{-1}

=(\frac{81}{4} - \frac{63}{2} - 18) - (\frac{1}{4} - \frac{7}{2} + 6) = -32

You forgot to subtract the second bracket

OP

Original post by TenOfThem

You did not use latex :smile:

:smile:

\displaystyle \int^3_{-1} x^3 - 7x - 6 dx = [\frac{x^4}{4} - \frac{7x^2}{2} - 6x]^3_{-1}

=(\frac{81}{4} - \frac{63}{2} - 18) - (\frac{1}{4} - \frac{7}{2} + 6) = -32

You forgot to subtract the second bracket

thank you. I forgot the minus sign. I did the question again and I was able to get the answer. thanks for your help.

next time I will use latex.

Quick Reply

Latest

Trending

Trending

Articles for you

Student story: studying for a career in law

Student story: studying for a career in law

Why I loved studying online

Why I loved studying online

How to save (and earn) more money while you're at university

How to save (and earn) more money while you're at university

What university is really like