Question

Find the principal solution of sino = 1/2

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Answer 1

Answer:

We know that

sinx=21=sin4π and by allied angles, we also know that 

sin(π−x)=sinx

∴sin4π=sin(π−4π)=sin43π

∴sin4π=sin3π4=21

such that 0<4π<2π and 0<43π<2π

∴ the required principal solution are x=4π and x=43π