f(x)=(2sinxcosx+5/2)/sinx+cosx=3cosx+5/(2sinx)π/12=15(省略度)cos(15)=cos(45-30)=cos45cos30+sin45sin30=√6/4+√2/4sin(15)=(√6-√2)/41/sin(15)=√6+√2f(π/12)=3(√6+√2)/4+10(√6+√2)/4=13(√6+√2)/4f...