- Sat May 02, 2015 8:26 pm
- Forum: Advanced Algebra ("pre-calculus")
- Topic: Complex Numbers Exponential Form
- Replies:
**1** - Views:
**14**

Coverct to rectanguala a+bi z = e^(3-i pi/2) Exponential form (starting about 2/3 of the way down here ) looks like: . . . z\, =\, r\, e^{i\theta} Use rules of exponents to convert your right-hand side expression into the normal format: . . . e^{3\, -\, \frac{i\,\pi}{2}} \, =\, e^3\, e^{-\frac{i\,\...

- Thu Apr 16, 2015 5:07 pm
- Forum: Geometry
- Topic: find the area of a square inscribed in a circle
- Replies:
**1** - Views:
**1036**

find the area of a square if it is inscribed in a circle in which one arc intercepted by a side of the square has length 12pi. Draw the square. Draw the circle inside. Draw horizontal and vertical lines through the center that split the square into four equal smaller squares. Label one of the small...

- Tue Mar 17, 2015 1:18 pm
- Forum: Intermediate Algebra
- Topic: Keep getting wrong answer
- Replies:
**1** - Views:
**313**

I get the wrong answer for 5 = 1/3(-2 + b) The way it's written means 5 = 1/[3(-2 + b)]. But I think you mean 5 = (1/3)(-2 + b). Is this right? I get b = 17 for the answer. But the book works it and comes up with an answer b = 17/3 You can check the answers by plugging them back into the original e...

- Tue Mar 17, 2015 1:14 pm
- Forum: Geometry
- Topic: area of a triangle
- Replies:
**1** - Views:
**1209**

Hi, I am have trouble with this problem. Find the area of triangle with angles 45-15-120. The side across from the 120 degree angle is 10. I need to solve without Trig. Similar problems have found 30-60-90 or 45-45-90 triangles in problem and used them to find the solution. But I am stumped....Ed H...

- Sat Mar 14, 2015 2:04 pm
- Forum: Pre-Algebra
- Topic: Payment formula
- Replies:
**2** - Views:
**422**

I'm trying to find the right formula to calculate mortgage installment. If I use a = j_0 r^n \frac{r-1}{r^{n+1}-r} i get results nearly the same as form online mortgage calculator , but not exactly the same. Where is the problem? We don't know what formula the calculator is using, what the variable...

- Tue Feb 17, 2015 1:10 am
- Forum: Discrete Math
- Topic: Express how many ways you can select a representative
- Replies:
**1** - Views:
**203**

Assume that a school has these three teams: Chess team with 10 members, Checkers team with 15 members, and College bowl team with 20 members. In how many ways can we select rep of the school if there should be: 1. exactly 1 representative from each team. Do the multiplication formula they showed yo...

- Wed Feb 11, 2015 3:36 am
- Forum: Beginning Algebra
- Topic: Linear Equations: Slope Problem.
- Replies:
**3** - Views:
**454**

I need help with this problem. I need to see if this problem will be an independent, inconsistent, consistent or dependent. These terms are for SYSTEMS of equations. The linear equation is: -X + 4y=4 X - 4y= -4 This is a SYSTEM of equations, not just one linear equation, as written. But then the x'...

- Wed Feb 11, 2015 3:33 am
- Forum: Beginning Algebra
- Topic: 2 Mechanics.
- Replies:
**8** - Views:
**456**

There are 2 mechanics by which the 1st one works for 75 an hr and then the second mech works for 55 an hour. Altogether they work 15 hours for an amount of 1025. What are the hours of both mechanics? You can learn how to set up this sort of thing here . First you translate the English into math: fi...

- Tue Feb 10, 2015 1:14 pm
- Forum: Intermediate Algebra
- Topic: Selection the solution and graph the inequality
- Replies:
**4** - Views:
**412**

It would be the second one: \dfrac{3}{8x}\, -\, \dfrac{1}{4x}\, <\, \dfrac{4}{5}\,\left(\dfrac{5}{32x}\, -\, 1\right) Thanks. Now what did you do with the LCM that didn't work? This is an inequality so you can't times through by a variable so you moved everything over to one side: 0\, <\, \...

- Tue Feb 10, 2015 1:10 pm
- Forum: Calculus
- Topic: finding volume of solids using cylindrical shells method
- Replies:
**2** - Views:
**281**

The question I have is about finding volume of solids using cylindrical shells method: The solid formed by rotating the region in the first quadrant bounded by y=0 and y=-x^3+x about the y=2 axis. To get the endpoints, do a graph . The factorization y = x(1-x)(1+x) says the zeroes are x=-1,0,+1. In...