sin(x+24度）＝sin(x+66度）求tanx

sin(x+24)=sin(x+66)
sin(x+24)=sin[90-(-x+24)]
sin(x+24)=cos(-x+24)
sin(x+24)=cos(x-24)
sinxcos24+sin24cosx=cosxcos24+sinxsin24
sinxcos24-sinxsin24=cosxcos24-sin24cosx
sinx(cos24-sin24)=cosx(cos24-sin24)
sinx=cosx
tanx=1

sin(x+24度）＝sin(x+66度），则说明（X+24°)+(X+66°）=180°加上360°的倍数，所以可求得2X=90°，这就不难求tanX的值了咯

sin(x+45-21)=sin(x+45+21)
x+45=90+k*180
x=45+k*180
tanx=1