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C3 Trig - Help please! Watch

1. How do you do the question I above? I assume you put it equal to pi/3 and -pi/3, without the modulus? I just don't know how to solve it from there on.
2. You have arcsin(x - 1) = +- Pi/3

Take sin's of each side.
3. (Original post by CalculusMan)
You have arcsin(x - 1) = +- Pi/3

Take sin's of each side.
That's where I got stuck. How do I "take sins" exactly? Does it become " x-1 = sin(pi/3) "?
4. The equations in blue you have written are correct , lets label the top one A, and the bottom one B.

Lets multiply both equations by

Coming to;

Working at A, get the sin to the other side,

which solves to

do the same for the other equation which would get the same except opposite sign.
5. Yes, and similarly for the other equation.

sin(arcsin(x)) = x for x between -1 and 1.
6. (Original post by Coda)
That's where I got stuck. How do I "take sins" exactly? Does it become " x-1 = sin(pi/3) "?
Yes thats true think of it like,

therefore

Or, think of it like this, to calculate the sin of 30 degrees you would due

When you have 0.5 and want to find the angle, on your calculator you would use,

Its more like the opposite action using the inverse.

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