## Search found 84 matches

Fri Nov 11, 2016 1:36 pm
Forum: Geometry
Topic: Find the area of a cross section of a cube.
Replies: 1
Views: 1221

### Re: Find the area of a cross section of a cube.

i have a dice. The lenghts of the sides of the dice is eight. The "sides" (also called "faces") are squares with areas. Do you mean that the length of an "edge" of the cube is 8, so the area of a face is 8^2 = 64? in the center of this cube there is a pass section inside the shape of a sqaure. What...
Sat Sep 03, 2016 7:09 pm
Topic: Need Some Help With Logarithms: solving solving 2^(2x+1)=3(2^x)-1
Replies: 1
Views: 619

### Re: Need Some Help With Logarithms: solving solving 2^(2x+1)=3(2^x)-1

If possible could someone try and talk me through solving 2^(2x+1)=3(2^x)-1 I've tried a number of things to work with it, and ended up finding a block after this first step, which I believed to be: 2(2^(2x))=3(2^x)-1 To get to this point, I think you did this on the left side: 2^{2x+1}\, =\, \left...
Sat Sep 03, 2016 7:04 pm
Topic: Simplifying: which is simpler x raised to 5/4 or x raised to the power of 5 inside a fourth root symbol?
Replies: 1
Views: 423

### Re: Simplifying: which is simpler x raised to 5/4 or x raised to the power of 5 inside a fourth root symbol?

which is simpler

x raised to 5/4 or x raised to the power of 5 inside a fourth root symbol (a square root with a 4)?
I don't know that either is "simpler". They're more different notations (rational powers versus radicals) than simplifications of each other.
Tue Jun 14, 2016 10:26 pm
Forum: Beginning Algebra
Topic: Liner graphing - Slopes - Problems with change in y being a fraction
Replies: 1
Views: 769

### Re: Liner graphing - Slopes - Problems with change in y being a fraction

Clearly I'm doing something wrong because the slope can't have a fraction over a denominator....
Why not? A fraction over a whole is just another number, right? Then you simplify or rearrange if you want a different format:

(2/3)/(2) = (2/3)/(2/1) = (2/3)*(1/2) = etc.
Sun Apr 03, 2016 10:07 pm
Topic: solving for x, given exponentials: 4e^2x + 5e^3x = 15
Replies: 7
Views: 1462

### Re: solving for x, given exponentials: 4e^2x + 5e^3x = 15

difference of probabilities-actual numbers are

(1-e^(-.2x))-(1-e^(-.16x))=.5

e^(-.16x)-e^(-.2x)=.5 solve for x
Wolfram Alpha still gives a complicated answer. Assuming your equation is right, then maybe the homework is expecting a numerical approximation instead of an algebraic solution.
Tue Mar 22, 2016 1:49 pm
Forum: Statistics
Topic: Simple probability question!
Replies: 2
Views: 871

### Re: Simple probability question!

There are 2 boxes, box A contains 20 white balls and 20 black balls, box B contains 10 white balls and 5 black balls. A box is chosen at random then a ball is taken at random from the chosen box, what is the probability that the ball is white? First I thought, it should be the probability of box A ...
Tue Mar 22, 2016 1:46 pm
Topic: Solving With Exponentials
Replies: 1
Views: 729

### Re: Solving With Exponentials

John would like to buy a new car for $10,000. His current car is worth$6,000 and will depreciate to 85% of it's value each year. This doesn't make sense. If its value is $6K and it "will depreciate to 85% of its value", then it will depreciate once to$5.1K. I think they probably meant to say that...
Mon Mar 07, 2016 1:59 pm
Forum: Beginning Algebra
Topic: Please review the forum rules before posting.
Replies: 2
Views: 10739

### Re: Please review the forum rules before posting.

...probably later on in the future. I'll be looking for ideas for exam materials and such. Will that be okay?
Probably it's fine but the forum is for helping people with homework so I don't know if there's anybody who can help you write tests.
Mon Feb 29, 2016 2:13 pm
Forum: Geometry
Topic: Multiplying square roots to find triangle sides
Replies: 1
Views: 1259

### Re: Multiplying square roots to find triangle sides

If I am multiplying 2 square root of 2 by 2 square root of two,... I'm taking this to mean \left(2\, \sqrt{ 2\,}\right)\, \left(2\, \sqrt{ 2\,}\right) . ...is the expression of that ( A ) 2 times square root of 4 ( B ) 4 times square root of 4 I think it should be "B". I get this: \begin{align}\lef...
Sun Feb 07, 2016 9:50 pm
Forum: Trigonometry
Topic: Need help with a problem: sin^2(x+1) = 3sin(cosx-sinx)+3
Replies: 1
Views: 1075

### Re: Need help with a problem: sin^2(x+1) = 3sin(cosx-sinx)+3

I don't know how to solve it. It's only one equation: sin^2(x+1) = 3sin(cosx-sinx)+3 Are you sure this is right? Because Wolfram Alpha can't do it exactly and if they can't do it exactly, I don't see how you're supposed to do it at all. To see what I mean, copy and paste this into your browser: htt...