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Which values for a and b will create infinitely many solutions for this system of equations? ax-y=8 2x+y=b

(a) compute the maclaurin polynomial m2(x) for f(x) = cos x. (b) use the polynomial of part (a) to estimate cos π 12. (c) use a calculator to compute the error made using the estimate from part (b) for the value of cos π 12. remember that the error is defined to be the absolute value of the difference between the true value and the estimate.

How to determine whether two known pairs of points are on the same line.