See Jia Earn Lim's answer to Do you have chocolate?'s Secondary 3 A Maths Singapore question

Jia Earn Lim's answer to Do you have chocolate?'s Secondary 3 A Maths Singapore question.

1 Upvotes

0 Downvotes

I haven’t done principle values in a while, I hope this is correct and helps you :)

Date Posted: 2 years ago

Comments 1 add a comment

Eric Nicholas K

2 years ago

Do note that for part (a), the principal angles for arcsin (inverse sin) are in the range -90° ≤ θ ≤ 90° in the case of degrees or -π/2 ≤ θ ≤ π/2 in the case of radians.

Correct for part (a) is -π/6, which is basically a fourth quadrant version of the basic reference angle π/6.

Do note that for part (b), the principal angles for arccos (inverse cos) are in the range 0° ≤ θ ≤ 180° in the case of degrees or 0 ≤ θ ≤ π in the case of radians.

Correct for part (b) is 2π/3, which is basically a second quadrant version of the basic reference angle π/3.