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Enter the mathematical formula directly and click the "Next" button to get the calculation answer.
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 cos(π/7)+cos(2*π/7)+cos(3*π/7)+cos(4*π/7)+cos(5*π/7)+cos(6*π/7) .
Question type: Mathematical calculation
Solution:
cos(π/7)+cos(2*π/7)+cos(3*π/7)+cos(4*π/7)+cos(5*π/7)+cos(6*π/7)
=cos0.448799+cos(2*π/7)+cos(3*π/7)+cos(4*π/7)+cos(5*π/7)+cos(6*π/7)
=cos0.448799+cos0.897598+cos(3*π/7)+cos(4*π/7)+cos(5*π/7)+cos(6*π/7)
=cos0.448799+cos0.897598+cos1.346397+cos(4*π/7)+cos(5*π/7)+cos(6*π/7)
=cos0.448799+cos0.897598+cos1.346397+cos1.795196+cos(5*π/7)+cos(6*π/7)
=cos0.448799+cos0.897598+cos1.346397+cos1.795196+cos2.243995+cos(6*π/7)
=cos0.448799+cos0.897598+cos1.346397+cos1.795196+cos2.243995+cos2.692794
=0.900969+cos0.897598+cos1.346397+cos1.795196+cos2.243995+cos2.692794
=0.900969+0.62349+cos1.346397+cos1.795196+cos2.243995+cos2.692794
=0.900969+0.62349+0.222521+cos1.795196+cos2.243995+cos2.692794
=0.900969+0.62349+0.222521+-0.222521+cos2.243995+cos2.692794
=0.900969+0.62349+0.222521+-0.222521+-0.62349+cos2.692794
=0.900969+0.62349+0.222521+-0.222521+-0.62349+-0.900969
=1.524459+0.222521+(-0.222521)+(-0.62349)+(-0.900969)
=1.74698+(-0.222521)+(-0.62349)+(-0.900969)
=1.524459+(-0.62349)+(-0.900969)
=0.900969+(-0.900969)
=0
Answer:cos(π/7)+cos(2*π/7)+cos(3*π/7)+cos(4*π/7)+cos(5*π/7)+cos(6*π/7)=0
Note: Radian
☆1 arithmetic calculations
[1/1 Formula]
Work: Calculate the value of equation cos(π/7)+cos(2*π/7)+cos(3*π/7)+cos(4*π/7)+cos(5*π/7)+cos(6*π/7) .
Question type: Mathematical calculation
Solution:
cos(π/7)+cos(2*π/7)+cos(3*π/7)+cos(4*π/7)+cos(5*π/7)+cos(6*π/7)
=cos0.448799+cos(2*π/7)+cos(3*π/7)+cos(4*π/7)+cos(5*π/7)+cos(6*π/7)
=cos0.448799+cos0.897598+cos(3*π/7)+cos(4*π/7)+cos(5*π/7)+cos(6*π/7)
=cos0.448799+cos0.897598+cos1.346397+cos(4*π/7)+cos(5*π/7)+cos(6*π/7)
=cos0.448799+cos0.897598+cos1.346397+cos1.795196+cos(5*π/7)+cos(6*π/7)
=cos0.448799+cos0.897598+cos1.346397+cos1.795196+cos2.243995+cos(6*π/7)
=cos0.448799+cos0.897598+cos1.346397+cos1.795196+cos2.243995+cos2.692794
=0.900969+cos0.897598+cos1.346397+cos1.795196+cos2.243995+cos2.692794
=0.900969+0.62349+cos1.346397+cos1.795196+cos2.243995+cos2.692794
=0.900969+0.62349+0.222521+cos1.795196+cos2.243995+cos2.692794
=0.900969+0.62349+0.222521+-0.222521+cos2.243995+cos2.692794
=0.900969+0.62349+0.222521+-0.222521+-0.62349+cos2.692794
=0.900969+0.62349+0.222521+-0.222521+-0.62349+-0.900969
=1.524459+0.222521+(-0.222521)+(-0.62349)+(-0.900969)
=1.74698+(-0.222521)+(-0.62349)+(-0.900969)
=1.524459+(-0.62349)+(-0.900969)
=0.900969+(-0.900969)
=0
Answer:cos(π/7)+cos(2*π/7)+cos(3*π/7)+cos(4*π/7)+cos(5*π/7)+cos(6*π/7)=0
Note: Radian