Melody

@@ End of Day Wrap - Monday 5/5/14   Sydney, Australia Time 21:40

Hi all,

Great answers were provided by Bertie, Alan, CPhill, admin, and Rom.  Thanks all. 

A nice thank you was given by Mathcalc.  We always appreciate it when we are thanked for our efforts. 

We now have a question watchlist that we have individual control over.  I expect this will be a really great addition. Thank you Andre.

Again I had a lot of problems opening this thread. I had to reopen the forum before I could get access!

All member questions have been answered but there are a few anonymous ones that have not been answered yet.  There are also a couple of questions that have not been ticked off because I would like them to be checked.

Enjoy the rest of your day.

Melody.

Do you mean a triangular prism?

Volume = area of triangular base x depth

Volume = 1/2 * base * perpaendicular height * depth  (units cubed)

$${\frac{\left(-{\mathtt{3}}\right)}{-{\mathtt{13}}}} = {\frac{{\mathtt{3}}}{{\mathtt{13}}}} = {\mathtt{0.230\: \!769\: \!230\: \!769\: \!230\: \!8}}$$

You can only find the log of a positive number so

$$4x-1>0 \\
4x>1\\
x>0.25\\$$

and

$$8x^2+26x-7>0\\
(2x+7)(4x-1)>0$$

consider the parabola

y=(2x+7)(4x-1)

This is a concave up parabola with roots x=-7/2 and x=1/4  

You should sketch the parabola.

The parabola has positive y values when x>1/4 and when x<-7/2

but we already know that x must be >0.25

therefore the expression is undefined when $$x\le 0.25$$

(Are other mathematicians happy with this?)

Kitty is correct but if you look at the bottom right of your page, the second sticky topic is 

"How do I  type in fractions."  There is more information in there.

All you have to remember Kitty is that if the $$\sqrt{\:\:\: }$$  is written in the question the answer is positive.

If you insert the $$\sqrt{\:\:\: }$$  yourself as a part of a solution then there are two solutions. One positive and one negative.

so

x-10=+3

x=13

 I'll give you your points now but please fix your answer Kitty. 

$$\frac{18x^5}{2x^4}\\\\
=9x$$

$$\frac{(2x^2)^3}{4x}\\\\
=\frac{8x^6}{4x}\\\\
=2x^5$$

This is the graoh of y=ln(x)

You can see on the graph that if x is negative there is NO value of y

The domain is X>0

6 to the power of 7 = 6^7 = $$6\:x^y\:7$$