I could use some help solving some problems.

[mathisconfusing101]

unfortunately I don't have a choice. I will be a senior this year.. and need this course for graduation.. and for college. Along with this geometry over the summer... i have to take algebra 2 in the fall. I havent understood math since like 8th grade... so im seriously screwed. I know I should calm down, but I just cant afford to fail this course again...

heres a sample of some of the problems that i can't quite do:

1. A refrigerator has a width of 3 feet. The angle of elevation from the bottom corner to the opposite corner is 65 degrees. What is the height of the refrigerator?

2. If the height of a refrigerator is 6 feet and the base is 3 feet, find the angle of elevation.

3. <img src="http://ns1.novelstars.com/files/geometryv2/sub20-3.jpg">Suppose c=12.3 and mÐB=55°. Find a.


Please help me!

[zaza]

Welcome to the Forums



This is trigonometry. I'm afraid there is no way around it but to learn the three basic trig functions, namely Sine, Cosine and Tangent. They are defined as follows:

For a right-angled triangle with a marked angle, the three sides are labelled Opposite (opposite the angle), Adjacent (the short side that forms part of the angle) and Hypotenuse (the longest side of the triangle, also forms part of the angle).

Sin(x) = Opposite / Hypotenuse

Cos(x) = Adjacent / Hypotenuse

Tan(x) = Opposite / Adjacent


This is the definition of Sin, Cos and Tan. Some people remember them by the mnemonic "SOHCAHTOA".

So in your fridge examples, the angle of elevation is from the bottom corner to the top corner. So the Adjacent side is the width of the fridge, the Opposite side is the height of the fridge and the Hypotenuse is the length of the diagonal from bottom left to top right (or bottom right to top left!).

Given the value of the angle and the length of Adjacent, you can use one of the above trigonometric identities to work out the length of Opposite. (Hint: use Tan...)

Given the values of Opposite and Adjacent you can work out the angle using one of the identities above.


Part 3 doesn't seem to appear.


Try parts 1 and 2 and see what you get. But I guarantee that you need to sit down and learn these trig identities. There is no alternative.


zaza

[Greek2Me]

If you're really interested in learning trig, here are links to tutorials for basic "right angle" trig. The first shows how to make a "Trig Tool", which elimininates memorizing a lot of formulas, the next two show how to USE it. There are quiet a few examples, and all it REALLY takes is a little patience and PRACTICE. Trig REALLY isn't that hard.

http://www.ehow.com/how_5520340_memo...sing-mind.html

http://www.ehow.com/how_5227490_pass...own-sides.html

http://www.ehow.com/how_5428511_pass...wn-angles.html

[jemidiah]

(c) is another application of the definitions Zaza gave, along with some equation solving.

Unfortunately, it's probably not a good idea to learn all of introductory trig over a forum, or even online. Of course we'd be happy to help with specific problems or topics as they come up.

For your more general problem of having trouble with math you have to take, I see a few options:

• Find and pay for a tutor (if you have the money)
• Find a math teacher to spend extra time with you, in place of a tutor
• Do extra studying with a friend who is also struggling
• Do extra studying on your own before you take the classes
• Do extra studying on your own while you take the classes

In my experience, a single human teaching another single human one-on-one is the best way of learning math. You get to go at your own pace, and the tutor can point out mistakes as they happen, instead of a week later when they crop up in another topic. That's why I suggested a tutor first, and a surrogate tutor second.

If you're not willing or able to find a tutor, you're left with studying with a non-tutor or on your own. Perhaps a friend of yours is in a similar situation. Studying together can sometimes be really effective at motivating both people. Of course you have to be careful to stay productive. I could see regular study sessions where you both read a section in your course's textbook, and stop each other when you get confused. Hopefully, you aren't often confused on the same things.

If you're left with studying on your own, I can see two major possible futures:

The first is that, a semester in advance, you get the book for your course and go through it. By that I mean every night you read 1 section. Don't skip any nights, or you'll run a large risk of breaking the habit entirely. If you find yourself lost, try to do a problem in the area you don't understand--this is to help you spot where things stopped making sense, so you can search for that material in the section. If you've been keeping up, you shouldn't be so lost as to keep this from helping. If you're stuck or confused on a section, seek help quickly so you don't stall. This method would require quite a bit of discipline on your part, but it's cheap, you can go at your own pace, and you don't run the risk of falling behind in the class itself. You could replace going through the book by taking online tutorials, or a number of things. It would probably be better to use the book the course will use, though. Perhaps you could even ask the teacher which sections they'll cover.

The second is that you study in some way outside of class, as you're taking it. This runs the risk of letting you fall behind, and math is very unforgiving about people who've fallen behind. That's why it was my fifth alternative.

Whatever you do, good luck!


Edit:

Trig REALLY isn't that hard.

While I agree, almost all of math really isn't that hard when viewed from the right perspective. From the right background of real analysis, this isn't hard.