已知α为锐角,且sin(α+15°)=,求:﹣2cosα﹣(π﹣3.14)0+tanα+()﹣1.
计算:(1)2×(-5)+23-3÷.
(2)先化简,再求值: – ,其中x = –3
(1)计算:3(–π)0– + (–1)2011