<p>@zma11rocks
3. I am 150% sure is I and III</p>
<p>III. 1/(x-1)+1
[inverse</a> of 1/(x-1)+1 - Wolfram|Alpha](<a href=“inverse of 1/(x-1)+1]inverse - Wolfram|Alpha”>inverse of 1/(x-1)+1 - Wolfram|Alpha)
Note : x/(x-1) = 1/(x-1)+1</p>
<ol>
<li><p>the answer choice is 0.06</p></li>
<li><p>Yes. It was f(x) = (x-3)^2+2</p></li>
<li><p>It was f(4.5)-f(-4.5) = 1-(-1) = 2.</p></li>
</ol>
<p>@piano68. The order of who calls might switch. So the 1/3 chance (either long distance or short distance or whatever) could be first.</p>
<p>@ExterH0peful I don’t understand what you’re doing with the link. I’ll work the problem out, and you tell me where I went wrong.</p>
<p>y=1/(x-1)+1. y(x-1)=1+(x-1). yx-y=x. y(x-1)=x. y=x/(x-1)
The inverse is </p>
<p>x=1/(y-1)+1. x(y-1)=1+(y-1). xy-x=y. x(y-1)=y. x=y/(y-1)</p>
<p>@zma11rocks
For the inverse, we can switch x and y then solve for y.
y = 1/(x-1) + 1
Switching,
x = 1/(y-1) + 1
Solving for y,
x(y-1) = 1+(y-1)
xy - x = y</p>
<p>xy - y = x
(x-1)y = x
y = x/(x-1)</p>
<p>You’re right. Dammnit, I didn’t remember to write the function in terms of y.</p>
<p>what was the q where there was y=sinx and a triangle and height, anyone?</p>
<p>which one was the question with log with the answer 1.2? i dont recall that one :/</p>
<p>hold on, why is everyone saying the standard deviation is .1? If this is the problem I think you’re talking about, it doesn’t stay the same when you add up all of the weights with .1= SD each, because you have to add the variances: .1^2 + .1^2 + .1^2 + .1^2 and find the square root of that to get .2
Edit: nevermind, the question asked about individual boxes not total. wow, I can’t read questions.</p>
<p>The log one was log(base 2)x = 1.2 , what is x. I used change of base formula, so Ln(x)/Ln(2) = 1.2
Ln(x) = 1.2<em>Ln(2)
x = e^1.2</em>Ln(2)</p>
<p>Whatever the value was…</p>
<p>^ it was log (base 2) x = -1.2</p>
<p>so 2^(-1.2) = 0.435</p>
<p>done.</p>
<p>and the period of the trig function was 4pi</p>
<p>How do you do this one: 35. Number of integers between -4 and 4, inclusive, that satisfy 2^m = 4^n?</p>
<p>God I love having a CAS. I just plugged that log one into my calculator and clicked solve haha too easy. </p>
<p>@joeykrug
You just plug in.
(4,2)
(0,0)
(2,1)
(-4,-2)</p>
<p>**** I think I put three…what did everyone else get…
I thought it asked for sets of or something…</p>
<p>^ The original question was actually the number of ordered pairs of integers (m, n) that satisfy the equation. First you simplify the problem:
2^m = 4^n
2^m = 2^(2n)
Thus, m = 2n
That means (-4, -2), (-2, -1), (4, 2), and (2, 1) work. Lastly, if both are 0, the equation is 1 = 1, a true statement.
The answer is five.</p>
<p>**** I missed that. What was the question with this 2x-2? </p>
<p>And did someone get 0.1 for a probability question pretty early on? </p>
<p>And what is this standard deviation of 8.4 talk? What was the question for that?</p>
<p>thanks i remember now</p>
<p>@justPhysics </p>
<p>1) The question for 2x - 2 asked something like:
f(g(x)) = h(x), where f(x) = x + 1 and h(x) = 2x - 1. What is g(x)?
Plugging in 2x - 2 for x in f(x), you get (2x - 2) + 1 = 2x - 1, which is h(x). I think that was the question.</p>
<p>2) It was a standard deviation question. They had four items, weighing 1.1, 1.1, 1.3, and 1.3 units and they said the standard deviation was 0.1. Then they placed the items into boxes weighing 2 units each. The question asked for the new standard deviation. The weights would be changed to 3.1, 3.1, 3.3, and 3.3, but there’s no need to calculate the new standard deviation manually. Instead, because you know each weight was increased by the same amount, the standard devotion must be the same: 0.1.</p>
<p>3) I don’t remember either… I just included it on the compiled list because I saw other people talk about it. Anyone remember the question?</p>
<p>^ Sorry, I meant h(x) = 2x - 2 for the first question in that response.</p>
<p>I remember but its blurry lol don’t remember the answer I put, I’m not gonna worry bout it since if I don’t remember it was probably easy</p>
<p>^ Agreed, it seems like an easier question.</p>
<p>Any guesses on the curve? The 2010 one was -6 for sure, maybe minus 7 because one guy confirmed raw 44 on the results thread and still got 800</p>
<p>@chemist12
Thanks for the explanation of the 2x -2 one; I am pretty sure I got it correct.</p>
<p>But for the 0.1 question I got that on that question but also on another one - the choices were like 1, 0.9, 0.1, 0.01 and something else. It was probability.</p>