Which equation represents a proportional relationship? a. y=5x+1 b. y=1/5x c. y= -5(x+1) d. y= -x

(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.

Use sigma notation to represent the following series for 9 terms.

Solve the system of equations. x=-2y+1 and x+2y=9. show work