(sin2x+4)/(cosx+1)=2.(cosx+3)(sinx+1)的值是?

(sin2x+4)/(cosx+1)=2.(cosx+3)(sinx+1)的值是?

（sinx)^2+4]/（cosx+1）=2,
（sinx)^2+4=2cosx+2,
1-(cosx)^2+4=2cosx+2,
(cosx)^2+2cosx-3=0,
cosx=-3(舍去),
cosx=1,此时sinx=0,
(cosx+3)(sinx+1)=4.