excel answers wrong!!!!!! (1 Viewer)

nanoose

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I have the excel General maths text book and all the answers I am getting for trigonometry are wrong (according to the book) although I am using the same method as the book..first I thought it was my calculator but then I tried another one and got the same anwer...Is it possible the text book answers are wrong cause I'm going crazy over simple trig...when i use the new century text book my method works but with this one and general math in a month the answers are weird...PLZ HELP SUM1
 

Dreamerish*~

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Post up a couple of questions, and I'll tell you what I get.
 

switchblade87

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shoo_nanoose said:
I have the excel General maths text book and all the answers I am getting for trigonometry are wrong (according to the book) although I am using the same method as the book..first I thought it was my calculator but then I tried another one and got the same anwer...Is it possible the text book answers are wrong cause I'm going crazy over simple trig...when i use the new century text book my method works but with this one and general math in a month the answers are weird...PLZ HELP SUM1
Perhaps your calculator is in the wrong mode, say in Radians (R) instead of Degrees (D). That will change your answer. Post some up and we'll see.
 

Riviet

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I bet my miniscule 4u knowledge on complex numbers that your calculator is not in deg mode. Textbooks usually only get 1 or 2 at the most wrong in the same excercise, unless that textbook really sucks, lol
 
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pLuvia

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It depends on the edition the textbook is in, 1st edition usually has lots of mistakes and the mistakes reduce as more editions are published
 

PC

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Another thing to look out for in the Excel book...

Quite a few of the Financial Maths questions on annuities have payments made at the beginning of each period. In the General Maths course, annuities always have payments made at the END of each period. The formulas given on the formula sheet only work for payments made at the end of each period.

So ... don't get too freaked out by these questions if you can't seem to figure out the answer at the back of the book!
 
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I can never clearly tell when to use PV/FV, usually PV is if $200000 made over 10 years at 5% pa what was the monthly repayments, right?
 

PC

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If you have a loan (i.e. making repayments) then you'll always use the PV formula, and the amount of the loan (the amount borrowed) is the PV. Use the formula to work out M, monthly payments.

If you're investing money, then it's a little more complicated:
1. If you're just putting a single sum of money away to start with, then it's Compound interest.
2. If you're making a series of regular payments, then it's an annuity so you use FV formula.

But ... if you're thinking about making regular payments and you want to look at the option of a single payment which will grow to the same amount, then you use PV.

See ... complicated.
 

Riviet

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Too bad you can't take them into the extension maths exams.
 

PC

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If you're doing Maths Extension, I reckon you probably don't need calculators anyway. It's all calculus and proofs and leaving things in terms of π.

Maybe you can fudge a curve sketch here or there.
 

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