How do you find the exact value of #arctan(1) + arctan(2) + arctan(3) #?

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Answer 1 · 2015-06-26T03:13:47

Answer is 0.

#arctanx+arctany+arctanz=arctan##(x+y+z-xyz)/(1-xy-yz-zx)#

Let x=#1#,#y=2#, #z=3#

#arctan(1)+arctan(2)+arctan(3)=#

#=arctan##((1)+(2)+(3)-(1*2*3))/(1-(1*2)(2*3)(3*1)#

#=arctan(0/(-35))#

#=arctan(0)#

#=arctan(tan0))#[from angle table]

#=cancel(arctan)cancel(tan)((0))#

#=0#