The Integral of 2xdx?
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This is only for those who can remember simple Calculus. If not familiar with Calculus, you would describe this in English as the integral of 2x with respect to the change in x evaluated from 10 to 13. The solution is x Squared (i.e. x*x) evaluated from 13*13 - 10*10 or 169-100. Thus resulting in the ultimate answer to the question about Life the Universe and Everything 69 minus 27 equals 42. This is a well-documented answer to the ultimate question of 'Life the Universe and Everything'.