trig eqn (1 Viewer)

[ibrian]

3cos@ - 4sin@ = 5 ( -pi < @ < pi) answer to 2 dp

i know you gotta transform it in Rcos(@+a) but when you find ur alpha (a), is it meant to be in degrees or rads :/

 

[oly1991]

it can be any

 

[Top Secret]

it can be any

+1

Though if you choose degrees, remember to convert the limit " -pi < @ < pi" into degrees.

 

[gurmies]

I'm not sure. I was told that if they give @ in radians, alpha should be in radians too.

 

[Top Secret]

I'm not sure. I was told that if they give @ in radians, alpha should be in radians too.

Don't think so. While it may be common sense to give final answer in required form, it is not necessary to use that form if working out if you don't feel comfortable with it.

I often use degrees to work out answers, then convert to required radian form.

But obviously ask your teachers if that's fine in the trials. Though in the HSC, use the required form throughout. Don't risk anything in the big one.

 

[Timothy.Siu]

should be rads.