# Math

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solve c(x)=x^2-40x+405

• Math -

C(x) = x^2 - 40x + 405 = 0,

x = ( 40 +- sqrt(400-1620)) / 2,
x = (40 +- sqrt(-20)) / 2,
x = (40 +- sqrt(20*-1)) / 2,
x = (40 +- 4.47i) / 2,

Solution Set:
x = 20 + 2.24i.
x = 20 - 2.24i.

• Math -

Correction:Replace 400 with 1600.

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