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- September 3rd 2010, 05:45 AMaeroflixchallenge set for solving trig equations
- September 3rd 2010, 05:48 AMProve It
a) Cross multiply, expand, move everything to one side, factorise and solve.

b) Multiply both sides by to get . Solve. - September 3rd 2010, 07:24 AMSoroban
Hello, aeroflix!

Quote:

Note that: . . . . (Think about it!)

So we have: .

Take the tangent of both sides:

. .

. .

. .

Quadratic Formula: .

Therefore: .

- September 3rd 2010, 02:33 PMaeroflix
yes i remember it,, its the same step just like the tan 60 degrres before right???? how did u know and figure out how to solve it?? whats your trick?

- September 3rd 2010, 09:09 PMProve It
Experience

- September 4th 2010, 08:16 AMaeroflix
here,, i solved letter b but its wrong

i ended up with 1/2 is not equal to 1/3

heres my solution or scratchhttp://img186.imageshack.us/img186/1323/qqqqqqqqqqy.png - September 4th 2010, 08:22 AMe^(i*pi)
You're trying too hard. Recall that

Thus

Multiply by

which is equal to

Solve the quadratic, I would use the difference of two squares to solve

Edit: Oops, I posted the answer to B not A which is in the quote

From what I can tell you're right (although confusing lol) up to . However, when you took the square root you didn't take the negative.

Taking the reciprocal of both sides:

I got answers of and (or ) as solutions (although only principal solutions because no range is defined in the question)

so discard that solution (from factoring out ) - September 4th 2010, 08:27 AMProve It
From

since

or

Case 1: Does ever equal ?

Case 2:

where

where

where . - September 4th 2010, 05:23 PMaeroflix
where did n pi / 2 came from?

- September 4th 2010, 05:34 PMaeroflix
what is the porper way t o solve sec^2x = sqaure root of 2