If a + b = 8 and ab = 15, find: a^3 + b^3

Question

KnowledgeBoat · Accepted Answer

Using the formula, [∵ (x \+ y)³ = x³ \+ y³ \+ 3xy(x \+ y)] So, ⇒ (a \+ b)³ = a³ \+ b³ \+ 3ab(a \+ b) Putting the value (a \+ b) = 8 and ab = 15, we get ⇒ (8)³ = a³ \+ b³ \+ 3 15 8 ⇒ 512 = a³ \+ b³ \+ 360 ⇒ a³ \+ b³ = 512 \- 360 ⇒ a³ \+ b³ = 152 Hence, the value of a³ \+ b³ is 152.

Mathematics

If a + b = 8 and ab = 15, find: a³ + b³

Identities

Related Questions

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Mathematics

If a + b = 8 and ab = 15, find: a3 + b3

Identities

Related Questions

If a + b + c = 11 and a2 + b2 + c2 = 81, find: ab + bc + ca.

If 3x - 4y = 5 and xy = 3, find: 27x3 - 64y3

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If 5x - 4y = 7 and xy = 8, find: 125x3 - 64y3

If a + b = 8 and ab = 15, find: a³ + b³

If a + b + c = 11 and a² + b² + c² = 81, find: ab + bc + ca.

If 3x - 4y = 5 and xy = 3, find: 27x³ - 64y³

If 3x + 2y = 9 and xy = 3, find: 27x³ + 8y³

If 5x - 4y = 7 and xy = 8, find: 125x³ - 64y³