trig question (1 Viewer)

[peterkim95]

i need help for a couple of questions.

1. tan 2x = 1 (-180 degrees (lessthanorequalto) x (lessthanorequalto) 180 degrees)

2. 2sin^2 3x = 1 (-180 degrees (lessthanorequalto) x (lessthanorequalto) 180 degrees)

3. tan x + 1 = 0 (-180 degrees (lessthanorequalto) x (lessthanorequalto) 180 degrees)

4. tan^2 2x =3 (-180 degrees (lessthanorequalto) x (lessthanorequalto) 180 degrees)

thanks

 

[pLuvia]

1. Since it's tan 2x, the domain will be for -2pi<x<2pi.
tan2x=1
2x=pi/4, 5pi/4
x=pi/8, 5pi/8

The next few are similar to the first one, give it a go and see if you can do it

 

[peterkim95]

1. Since it's tan 2x, the domain will be for -2pi<x><2pi.
tan2x=1
2x=pi/4, 5pi/4
x=pi/8, 5pi/8

The next few are similar to the first one, give it a go and see if you can do it

I was actually looking for answer using ASTC, using trig.

i'll have a go though


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[pLuvia]

I'm not sure what you mean, but since tan2x=1, we know from the ASTC that tan2x is positive in the 1st and 3rd quadrant so we simply apply that concept
tan2x=1
2x=pi/4 or pi+pi/4
=pi/4, 5pi/4
x=pi/8, 5pi/8

Is that what you meant?