Question

evaluate 72^3 using suitable identities

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Answer 1

Step-by-step explanation:

(70 + 2)³

Using the identity of -

• (a + b)³ = a³ + b³ + 3a²b + 3b²a

here,

a = 70

b = 2

Then,

(70 + 2)³

= (70)³ + (2)³ + 3(70)²(2) + 3(2)²(70)

= 3,43,000 + 8 + 29,400 + 840

= 3,73,248

Hence,

The value of (72)³ is 3,73,248

Formula Used -

• (a + b)³ = a³ + 3a²b + 3b²a + b³

Some related formulas -

• (a + b)² = a² + 2ab + b²
• (a - b)² = a² - 2ab + b²
• (a + b)(a - b) = a² - b²
• (a + b)³ = a³ - 3a²b + 3b²a - b³

Answer 2

Step-by-step explanation:

hope this answer helps you