Difficulty: Easy
Correct Answer: 0.86
Explanation:
Problem restatement
Compute the value of the fraction where the numerator is a3 − b3 with a = 0.96, b = 0.10, and the denominator is a2 + ab + b2.
Given data
Concept/Approach
Use the identity a3 − b3 = (a − b)(a2 + ab + b2). Dividing (a3 − b3) by (a2 + ab + b2) simplifies to a − b.
Step-by-Step calculation
[(0.96)3 − (0.10)3] ÷ [(0.96)2 + (0.96)(0.10) + (0.10)2] = 0.96 − 0.10= 0.86
Verification/Alternative
Direct substitution into the identity confirms immediate cancellation of the common factor.
Common pitfalls
Computing all powers numerically instead of recognizing the factorization shortcut.
Final Answer
0.86
Discussion & Comments