Question

Expand using formula: (2m - 5)³​

Answer 1

Step-by-step explanation:

8m³- 3 x 4m² x 5 + 3 x 2m x 25 - 125

>> 8m³ - 60m² + 150m - 125

Answer 2

$\sf\underline{\underline{ \large {Question :-}}}$

• Expand using formula: (2m - 5)³

$\sf\underline{\underline{ \large {Answer:-}}}$

• 8m³ - 60m² + 150m - 125

$\sf\underline{\underline{ \large {Using \: Identity :-}}}$

• $\sf\bigstar\pink{(a-b)^{3} \: = a^{3} - 3a^{2}b + 3ab^{2} - b^{3}}$
• Here,
• a = 2m
• b = 5

$\sf\underline{\underline{ \large {Solution :-}}}$

$\purple \bigstar \sf{(a-b)^{3} \: = a^{3} - 3a^{2}b + 3ab^{2} - b^{3}}$

• Putting the values in the identity

:$\sf\purple \mapsto{2m^{3} - 3 \times 2m^{2} \times 5 + 3 \times 2m \times 5^{2} - 5^{3}}$

:$\sf\purple\mapsto{8m^{3} - 3 \times 4m^{2} \times 5 + 3 \times 2m \times 25 - 123}$

:$\sf\purple\mapsto{8m^{3} - 3 \times 20m^{2} + 150m - 125}$

:$\sf\purple\mapsto\red{8m^{3} - 60m^{2} + 150m - 125}$