大家帮忙求下这2个角度是多少?∠arctan(-2/-2√3)和∠arctan(-2/2√3)

大家帮忙求下这2个角度是多少?∠arctan(-2/-2√3)和∠arctan(-2/2√3) arctan(-2)+arctan(-3)=? arctan(1/3)+arctan(1/2)的值为? arctanπ/2＝? arctan根号2是什么, 求arctan1/3+arctan(-2)的值 arctan1/3+arctan(-2)的值为 求值：sin[1/2arctan(-4/3)] 求arctan1/3+arctan(-2)的值. arctan(A/2)+arctan(A/5)=30 计算：arctan1/2-arctan(-2) 求证：arctan 1/2+arctan 1/5+arctan 1/8=π/4