4.11 The Maclaurin series expansion for cos x is 2 x4 cos x = 1 + 2 4! - x6 + 8! 6! Starting with the simplest version, cos x = 1, add terms one at a time to estimate cos(л/4). After each new term is added, compute the true and approximate percent relative errors. Use your pocket calculator or MATLAB to determine the true value. Add terms until the absolute value of the approx- imate error estimate falls below an error criterion conform- ing to two significant figures.