化簡[cos(α-π)*cot(5π-α)]/[sin(-2π-α)] ②sine*根號下(1+cot²;e)(e為第三象限角)

化簡[cos(α-π)*cot(5π-α)]/[sin(-2π-α)] ②sine*根號下(1+cot²;e)(e為第三象限角)

[cos(α-π)*cot(5π-α)]/[sin(-2π-α)]=[cos(π-α)*cot(π-α)]/[sin(-α)]=【-cosα(-cotα)】/(-sinα)=-cosα*(cosα/sinα)/sinα=-cot²;αsine*根號下(1+cot²;e)=sine*|1/sine|=-sin…