Melody

Yes I know what I answered.

I answered the question that was asked.

Good work Azsun.   

What is the exact volume of a cylinder whose radius is 9 feet and whose height is 26 feet?

Enter your answer, in terms of ππ , in the box.

The answer you got is approximate.

\(V= area\;of\;base\; * \;height\\ V= \pi r^2 \quad*\quad h\\ V= \pi *9^2 \quad*\quad 26\\ V= 81*26\pi\\ V= 2106 \pi\qquad feet^3\)

There are 5 choices for the first letter, 5 for the second and 5 for the third so that is  5^3 = 125 words

It says to answer in terms of pi so your answer is obviously not the one that they want.

verify that equation is an identity:

It depends on what you are allowed to use to verify it.... but..

1. sin(A+π) = -sinA

\(LHS=sin(A+\pi)\\ LHS=sinAcos\pi+cosAsin\pi \\ LHS=(sinA*-1)+(cosA*0)\\ LHS=-sinA\\ LHS=RHS\\ QED \)

2. tan(x+45) = (1 + tanx) / (1 - tanx)

\(LHS\\ =tan(x+45)\\ =\frac{tanx+tan45}{1-tanxtan45}\\ =\frac{tanx+1}{1-tanx}\\ =\frac{1+tanx}{1-tanx}\\ =RHS\\ QED \)

if f(x)=2x/x-5,

find f^-1(x).

That is a bit better :)

You have written

\(if\\ f(x)=\frac{2x}{x}-5\\ find \;\;f^{-1}(x).\)

But I expect you left out the brackets and you actually mean

\(if\\ f(x)=\frac{2x}{x-5}\\ find \;\;f^{-1}(x).\)

Be careful with those brackets. 

Let

  \(​​​​y=\frac{2x}{x-5}\\ \text{x cannot be 5}\\ \text{Now make x the subject}\\ yx-5y=2x\\ yx-2x=5y\\ x(y-2)=5y\\ x=\frac{5y}{y-2}\\ \text{Now for the inverse swap x and y over}\\ y=\frac{5x}{x-2} \)

So if

\(f(x)=\frac{2x}{x-5}\\then\\ f^{-1}(x)=\frac{5x}{x-2}\\ where\;\;x\ne2\)

Here are the graphs

The inverse fof a funtion is the reflection of the funtion in the line y=x

NOW LEARN FROM THIS AND TRY AND DO THE REST BY YOURSELF!

draw a pic and you will see that 

\(tan 20=\frac{x}{250}\\ x=250tan 20 \)

250*tan(20) = 90.9925585665

The wind is blowing at 91km/hour

Stop being so lazy quality Street.

Firslty you should be doing your own homework and just useing as as a learning tool.

NOT just getting people here to do your homework for you with multiple questions posted at the same time.

SECONDLY.

This is a simple question for you to TYPE in instead of sending answerers on a trip through your rabbit warren just to find your question!

TYPE YOUR QUESTIONS IN !!

OR  insert them as pictures if they are diagrams

If you must use the occasional link than use the link function that is available in the ribbon.

It is good that you just led the answerers to the original question, that is how it should  be done

BUT

In order to maximise your chance of an answer you need to include your question address with a link.