# Thread: hello all,can any help me in this questions..

1. ## hello all,can any help me in this questions..

hi friends,
plz i send in attachements a file contians questions need for sullotion plz help me i have test tommorow.

thnks.

2. Originally Posted by eman.kh
hi friends,
plz i send in attachements a file contians questions need for sullotion plz help me i have test tommorow.

thnks.
well, if you need this stuff for a test tomorrow, it would be more beneficial to you to tell us what you have tried and allow us to help you work through it.

for question one, you want $\int_{- \sqrt{3}}^{\sqrt{3}} \left( 3 - x^2 \right)~dx = 2 \int_0^{\sqrt{3}} \left( 3 - x^2 \right)~dx$

do you know why? do you see why i have those limits?

what have you tried for the others?

3. for question 5, use the quotient rule.

personally, i would rewrite as $f(x) = (2 - x)^{-1/2}$ and use the chain rule twice. then plug in x = 1

4. for question 6, you have:

$\frac {dx}{dy} - e^{y - x} = 0$ with $x(1) = 0$

rewrite:

$\frac {dx}{dy} = e^{y - x} = e^y \cdot e^{-x}$

$\Rightarrow e^x ~dx = e^y~dy$

now integrate both sides and continue

5. provided all the necessary conditions are fulfilled, the average value of a function $f(x)$ on a closed interval $[a,b]$ is given by:

$\mbox{Average Value} = \frac 1{b - a} \int_a^b f(x)~dx$

6. for question 10, a function is concave up on the interval its second derivative is positive

7. 1st thnkx alot for helping me really.
2nd i tried to answer this in papers and i don't have time to write in the forums that's why i put just the questions,and i alrready used the rules u told me really but at final i didn't find the answer.
so if u want can u comlete yr help with tel me the right answer 4 qustions.

thnks agian.