Really? This site is for real questions stop wasting time and electricity.

do pemdas. first parenthese exponents multiplication division addition subtraction.

First simplify the exponent since there are no parentheses, then add the rest, but it will not be simplified you will have three different terms then you have to factor it and make it equal to zero.  

274.579678782

Also I forgot the formula for circumference isn't really that its 2πr (two times pi times radius), but if you simplify that its essentialy πd

jello  jk its 4

4

The formula for the circumference is πd (pi times diameter).  First you apply that then since it is a semi-circle you divide it by 2 and there you get your answer!.

So it would be:

π(22) then you divide it by two.

Without the zero, it will take you forever. Even so, Zeus commands you be told where to find the Roman zero. He is not concerned you will finish before Sisyphus completes his task. The zero is inside Sisyphus’s boulder. Good luck!

Now, I must serve my master his lunch. He is having Pi.

khairete (fairwell)

how do u find the mean?

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The "mean" of a data set is just its average. An example may work better than a definition.  Let's suppose we have four test scores and we're trying to find their average.

Let's say the scores are 60, 75, 85 and 100.

I just add them up and divide the sum by the number of scores we have.

So

(60 + 75 + 85 + 100) / 4  = (320 / 4 ) = 80.

And that's their average.

yes!!! yes!!!

Hello there,

I think it is important that children everywhere can own a walrus of their own for example this is my pet Jerry

Sincerely,

Gib

$$\begin{array}{ccl}x^{3}+ax+b & = &(x-1)^{2}(px+q)\\ & = & (x^{2}-2x+1)(px+q)\\ & = & px^{3}+(q-2p)x^{2}+(p-2q)x+q \end{array}$$

For equality, we need

 $$p=1 \text{ and } q=2,$$

so

$$x^{3}+ax+b \rightarrow x^{3}-3x+2=(x-1)^{2}(x+2)$$

and the remainder after division by x+2 is zero.

Chris wrote; 

This one would be difficult to solve without a solving program....although we could use some Calculus techniques to get an approximation, like Alan did. However, since you're asking a trig question, I might assume that you haven't taken Calculus, yet.

Using Wolfram, the solutions (in rads) are -2.13105 (-122.1°) and .585321 (33.54°)

We should note that Wolfram's results are also approximate.

An alternative, non-calculus based technique, would be a binary section technique.  Choose two values of opposite sign either side of a solution (use the graph to come up with initial choices).  Then halve the interval and see if f(x) is sufficiently close to zero. If it isn't but is positive, replace the previous positive value by this new one (similarly, if the new one is negative, replace the previous negative value by the new one) and keep repeating this process until f(x) is within some pre-specified tolerance of zero.

Plot a graph of the left-hand side:

It looks like there is a solution between x = 3 and x = 4.    Let f(x) = 5.4^x - 4.9^x - 105 and find the value of x that makes this zero.

You need to adopt a numerical method, like the ones noted here:  

The solution is (approx) x = 3.683447

If it's 8 o'clock and I add 8 hours it's 4 o'clock.

Alan, did you do that whole answer in Texmaker and then copy it over?

I did (well, the LaTeX bit - not the graph!) and it didn't work perfectly (the first few lines aren't in the same position as in Texmaker)!

The only factors of 21 are 1,3,7,and 21.

Out of those the only factors of 40 is 1 and 1 doesn't count.

So 21 and 40 have no common factors

therefore

the lowest common denominator is 

$${\mathtt{21}}{\mathtt{\,\times\,}}{\mathtt{40}} = {\mathtt{840}}$$

Alan, did you do that whole answer in Texmaker and then copy it over?

if x^2+(3*sin(x))-2=0 then what is the value of x?

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This one would be difficult to solve without a solving program....although we could use some Calculus techniques to get an approximation, like Alan did. However, since you're asking a trig question, I might assume that you haven't taken Calculus, yet.

Using Wolfram, the solutions (in rads) are -2.13105 (-122.1°) and .585321 (33.54°)

I think that's it.......

it is sarah obama.

Let f(x)=x²+3sin(x)-2.  We want the value(s) of x that make f(x)=0.

First let's plot a graph of the function:

We can see there are two solutions to f(x) = 0.  Because of the sin(x) term we need to solve this numerically.  One way of doing this is to use the Newton-Raphson method:

$$\textbf{Newton-Raphson numerical method}.\\
$$f(x)=x^2+3sin(x)-2$$\\
$$f'(x)=2x+3cos(x)$$

Guess an initial value for $x$ call it $x_0$. Then iterate towards a solution as follows:
$$x_{n+1}=x_n-\frac{f(x_n}{f'(x_n)}$$ \\

Because there are two solutions here, we need to do this twice with a different guess each time. From the graph we can see that $x_0=-2$ and $x_0=1$ might be good guesses.\\
Because Newton-Raphson tends to converge quickly, we probably don't need to iterate many times. Here after about 4 iterations we converge on $$x=-2.1310748$$ and $$x=0.5853206$$ from our two guesses, which looks consistent with the graph above!$$

Dear Anonymous,

I'm trying to do as you requested.....but I'm running into a slight problem......I'm still looking for the Roman Numeral representation for "0"  !!!  

However.....if I DO find it, I should be finished by lunchtime......or so..........

Hi Professor,

It is great that you are answering questions but you messed that one up a little.

$$(5-(5-2(5-6)+7))+2\\

=(5-(5-2(-1)+7))+2\\

=(5-(5+2+7))+2\\$$

2*-1 is done BEFORE 5-2

Thanks Alan I will definitely try that.

I am quite comfortable with typing straight into the forum but the preview display is very poor.

I expect I would rather do it your way.  Thanks.

[5 - (5 - 2(5 - 6) + 7)] + 2= ?

[5 - (5 - 2(-1) + 7)] + 2= ?

[5 - (+3(-1) + 7)] + 2= ?

[5 - ((-1)+10)] + 2= ?      +3 + +7 = +10

[5 - (+9) + 2= ?                -1 + +10 = +9

[7- (+9)= ?                        5 + 2 =7

[7- (+9)= ?               + (+) - = -      -9 + +7 = -2

? = -2