CUET Preparation Today
CUET
General Test
Quantitative Reasoning
Algebra
If a3 - b3 = 2349, a - b = 9, then find the value of (a + b)2 - ab.
196
250
261
274
Formula → a3 - b3 = (a - b) (a2 + b2 + ab)
2349 = 9 (a2 + b2 + ab)
we can write a2 - b2 + ab as ⇒ (a + b)2 - ab
So, (a + b)2 - ab = \(\frac{2349}{9}\) = 261