cot43°×cot44°×cot45°×cot46°×cot47°应该怎么算?

cot43°×cot44°×cot45°×cot46°×cot47°应该怎么算?
cot43°×cot44°×cot45°×cot46°×cot47°应该怎么算?

cot43°×cot44°×cot45°×cot46°×cot47°应该怎么算?
tanA=cot(pi/2-A)=1/cotA
因此有cotA*cot(pi/2-A)=1
故cot43°×cot47°=1
cot44°×cot46°=1
所以cot43°×cot44°×cot45°×cot46°×cot47°＝cot45°=1