已知(1+sinx)/cosx= -1/2 ,则cosx/(sinx-1)的值为? 请写出解答过程!谢谢!

热心网友

cosx^2=1-sinx^2=(1+sinx)(1-sinx)=-(1+sinx)(sinx-1)所以(1+sinx)/cosx = -cosx/(sinx-1)所以cosx/(sinx-1) = 1/2