Hi guyz, as we know we have some known relations in the trigonometric functions like(adsbygoogle = window.adsbygoogle || []).push({});

sin(2x)=2sin(x)cos(x) and sin(x/2)=1/2-1/2 cos2x

My question is are there similiar formulas for arcsin and arccos?

I know those only !

arcsin x =ln(ix-sqrt(1-x^2))

arccos x =ln(-ix-sqrt(1-x^2))

I'm working in electrodynamics, and i reached an integral for the kinetic energy and the answer should be mc^2-mc^2, but i'm getting arcsin !!

i knew the answer already about the energy, but i don't this i should neglect the problem of the damn inverse function,

Can any one help and tell me some formulas?

Thanks...

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# Trigonometric functions like sin(2x)=2sin(x)cos(x)

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