Question

factorise-121m^2-100n^2​

Answer 1

ANSWER:

• Factorisation of the above expression (11m-10n)(11m+10n).

GIVEN:

• 121m²-100n²

TO FIND:

• Factorise the above expression.

FORMULA USED:

• a²-b² = (a+b)(a-b)

SOLUTION:

= 121m²-100n²

= (11m)² -(10n)²

= (11m-10n)(11m+10n)

NOTE:

Some important formulas:

(a+b)² = a²+b²+2ab

(a-b)² = a²+b²-2ab

(a+b)(a-b) = a²-b²

(a+b)³ = a³+b³+3ab(a+b)

(a-b)³ = a³-b³-3ab(a-b)

a³+b³ = (a+b)(a²+b²-ab)

a³-b³ = (a-b)(a²+b²+ab)

(a+b)² = (a-b)²+4ab

(a-b)² = (a+b)²-4ab