Use the formula to expand-6 7 m-4 n3

We know that (x + y)3 = x3 + 3x2y + 3xy2 + y3. Comparing (7m + 4n)3 with (x + y)3, we get: x = 7m and y = 4n Substituting these in the above formula: (7m + 4n)3 ...

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Byju's Answer

Standard VIII

Physics

Static Friction

Use the formu...

Question

Use the formula to expand:

(6) (7m + 4n)³

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Solution

We know that (x + y)³ = x³ + 3x²y + 3xy² + y³.
Comparing (7m + 4n)³ with (x + y)³, we get:
x = 7m and y = 4n
Substituting these in the above formula:
(7m + 4n)³ = (7m)³ + 3 × (7m)² × 4n + 3 ×7m ×(4n)² + (4n)³
= 343m³ + 588m²n + 336mn² + 64n³

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Use the formula to expand: (6) (7m + 4n)3

We know that (x + y)3 = x3 + 3x2y + 3xy2 + y3. Comparing (7m + 4n)3 with (x + y)3, we get: x = 7m and y = 4n Substituting these in the above formula: (7m + 4n)3 = (7m)3 + 3 × (7m)2 × 4n + 3 ×7m ×(4n)2 + (4n)3 = 343m3 + 588m2n + 336mn2 + 64n3

Use the formula to expand:

(6) (7m + 4n)³

We know that (x + y)³ = x³ + 3x²y + 3xy² + y³.
Comparing (7m + 4n)³ with (x + y)³, we get:
x = 7m and y = 4n
Substituting these in the above formula:
(7m + 4n)³ = (7m)³ + 3 × (7m)² × 4n + 3 ×7m ×(4n)² + (4n)³
= 343m³ + 588m²n + 336mn² + 64n³