Hello i know the maclaurin polynomial 4 terms is P4 1 x 1

Solution

e^x = 1 + x + x^2/2! + x^3/3! .... by Taylor or Maclaurin series put x = 1 e = 1 + 1 + 1^2/2! + 1^3/3! ...... but the given series is 1 - x + x^2/2! - x^3/3! + x^4/4! .... in this series if we put x = -1 we get 1 + 1 + 1^2/2! + 1^3/3! ... which is same as \'e\' as shown above hence you got to put x = -1 and calculate upto 4 terms to get an approximate value of \'e\'