Question

How do you solve 2sinx-1=0 without a calculator?

Answer 1

\[2sinx = 1\]

\[sin(x) = \frac{1}{2}\]

What value of sin is 1/2??

Answer 2

sinx=1/2 so sinx=sin30 so x=30 degrees

Answer 3

Add 1 on both sides
2sinx = 1
divide 2 on both sides
sinx = 1/2
x= \(sin^{-1} \frac{1}{2} \)

Answer 4

do you have to draw a graph of sin to find these values for sinx=0.5?

Answer 5

Thank you for such quick replies :)

Answer 6

So,

\[sin(x) = sin ( \frac { \pi }{6}) \implies x = \frac{\pi}{6}\]

Answer 7

you can also commit to memory this triangle