Question

Use differentials to approximate the value of the expression. Compare your answer with that of a calculator. (Round your answers to four decimal places.) (8.99)3 using differentials

Answer 1

Answer:

726.572699

Step-by-step explanation:

According to differentials

(x+Δx)³ = x³ + 3x²Δx + 3x(Δx)² + (Δx)³ (Using binomial expansion)

Using this formula to solve (8.99)³, this can also be written as;

(8.99)³ =  (9-0.01)³ where

x = 9

Δx = -0.01

Substitute this vales into the differential expression above

(9+(-0.01))³ = 9³ + 3(9)²(-0.01) + 3(9)(-0.01)² + (-0.01)³

(9+(-0.01))³ = 729 + (243)(-0.01) + 27(0.0001) + (-0.000001)

(9+(-0.01))³ = 729-2.43+0.0027-0.000001

(9+(-0.01))³ = 729-2.43+0.0027-0.000001

(9+(-0.01))³  = 726.572699

Hence 8.99³ = 726.572699 (Using differential)

Using calculator;

8.99³ = 726.572699