<p>(x-3)(x+7)=0 – One of the factors needs to be zero. If x = -7, (x+7) equals 0, in that case (x-3) equals -10. So, B</p>
<p>Intersection Q: k intersects m, p and r at exactly 3 points. The same goes for l. k and l don’t intersect. Therefore D (6).</p>
<p>Maxima/Minima Q: Well, I did part of this with calculus, so it might not be very helpful. Differentiating the first function we get f’(x) = 4x^3-6x^2. Setting it equals 0 gives x = 0 and x = -1.5. f(0) < f(1.5), so the reqd. maxima is at x = 1.5, roughly equal to 6.7. The second function has two terms with an even power of x, so those two terms are >= 0. Therefore the minima is -4. The difference is 10.7. If you have a graphing calculator, you don’t need to go into all this trouble though.</p>
<p>i don’t actually but thanks a bunch!</p>
<p>oh sorry… 49 please</p>
<p>You can either graph and find maximum or differentiate.</p>
<p>y = (240-10n)(2+0.25n)
y’ = (240-10n)(0.25) + (2+0.25n)(-10)
y’ = 60 - 2.5n -20 -2.5n
y’ = 40 - 5n</p>
<p>y’ = 0 <=> 40-5n = 0 => n=8</p>
<p>Answer is E.</p>
<p>Answer is E, all you have to do is type the whole equation in the calculator, zoom fit and find max</p>
<p>that’s differentiation? what did you do there?</p>
<p>I thought this is how you diff:
[How</a> to Differentiate Polynomials (with Pictures) - wikiHow](<a href=“http://www.wikihow.com/Differentiate-Polynomials]How”>How to Differentiate Polynomials: 10 Steps (with Pictures))</p>
<p>I DON’T HAVE A GRAPHING CLAC!</p>
<p>plus. i thought you don’t use that in sat math1 anyway?!</p>
<p><a href=“Dropbox - Error - Simplify your life”>https://www.dropbox.com/s/xwfk8xj5iyz18dw/310520132008.jpg?m</a></p>
<p>the funny part abt this one… is that i did right and the forgot how i did it now</p>
<p>I think I’m just too paranoid hu?</p>
<p>Oh god. I guess you haven’t taken calculus.</p>
<p>The link you provided in #9 is basic differentiation with polynomials. It works for this question too, you just have to distribute first.</p>
<p>I used the product rule.
[Product</a> Rule, Quotient Rule, and Chain Rule Tutorial](<a href=“http://www.1728.org/chainrul.htm]Product”>Product Rule, Quotient Rule, and Chain Rule Tutorial)</p>
<p>do i have to know all this for tomorrow?!!?!?!!?!</p>
<p>So, do you need help with the pond one?</p>
<p>
</p>
<p>No. Not for Math 1. If you have just polynomial differentiation down, you should be fine. Just distribute first and they differentiate according to power rule.</p>
<p>Remember, the derivative is just the function’s rate of change. When the rate of change changes sign, it means that the function changes from increasing to decreasing or vice versa.</p>
<p>rate of expansion = 3 ft/s</p>
<p>Increase: (C at 3s) - (C at 1s)</p>
<p>Circumference at end of 3rd second = 2pi9
Circumference at end of 1st second = 2pi3</p>
<p>Increase= 2pi9-2pi3 = 2pi(9-3) = 2pi(6) = 12pi</p>
<p>okay so i was thinking </p>
<p>the first ripple is x</p>
<p>second ripple x+3
third ripple x+6</p>
<p>difference 2pi(6) (2nd inc in radius ) - 2pi(3) (1st inc in radius) = 6pi</p>
<p>or </p>
<p><a href=“Dropbox - Error - Simplify your life”>https://www.dropbox.com/s/9vkxu5dyhu9f7r2/310520132009.jpg?m</a></p>
<p>so:
Circumference at end of 3rd second = 2pi9
Circumference at end of 1st second = 2pi6 </p>
<p>btw you’re right. just wanna know why I AM worng</p>
<p>The radius at end of first second is 3.</p>
<p>oh wait… i got 50
it’s d :D</p>
