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It supports mathematical functions (including trigonometric functions).
Current location：Mathematical operation > History of Mathematical Computation > Answer
Overview: 1 questions will be solved this time.Among them
☆1 arithmetic calculations
[1/1 Formula]
Work: Calculate the value of equation tan(π/5)*tan(2*π/5)+tan(2*π/5)*tan(3*π/5)+tan(3*π/5)*tan(4*π/5) .
Question type: Mathematical calculation
Solution:
tan(π/5)*tan(2*π/5)+tan(2*π/5)*tan(3*π/5)+tan(3*π/5)*tan(4*π/5)
=tan0.628319*tan(2*π/5)+tan(2*π/5)*tan(3*π/5)+tan(3*π/5)*tan(4*π/5)
=tan0.628319*tan1.256637+tan(2*π/5)*tan(3*π/5)+tan(3*π/5)*tan(4*π/5)
=tan0.628319*tan1.256637+tan1.256637*tan(3*π/5)+tan(3*π/5)*tan(4*π/5)
=tan0.628319*tan1.256637+tan1.256637*tan1.884956+tan(3*π/5)*tan(4*π/5)
=tan0.628319*tan1.256637+tan1.256637*tan1.884956+tan1.884956*tan(4*π/5)
=tan0.628319*tan1.256637+tan1.256637*tan1.884956+tan1.884956*tan2.513274
=0.726543*tan1.256637+tan1.256637*tan1.884956+tan1.884956*tan2.513274
=0.726543*3.077683+tan1.256637*tan1.884956+tan1.884956*tan2.513274
=0.726543*3.077683+3.077683*tan1.884956+tan1.884956*tan2.513274
=0.726543*3.077683+3.077683*-3.077679+tan1.884956*tan2.513274
=0.726543*3.077683+3.077683*-3.077679+-3.077679*tan2.513274
=0.726543*3.077683+3.077683*-3.077679+-3.077679*-0.726543
=2.236069+3.077683*(-3.077679)+(-3.077679)*(-0.726543)
=2.236069+(-9.47212)+(-3.077679)*(-0.726543)
=2.236069+-9.47212+2.236066
=-7.236051+2.236066
=-4.999985
Answer:tan(π/5)*tan(2*π/5)+tan(2*π/5)*tan(3*π/5)+tan(3*π/5)*tan(4*π/5)=-4.999985
Note: Radian