Question

Factorise 121- 4a²
please help me with this question..​

Answer 1

Answer:

Theory : A difference of two perfect squares, A2 - B2 can be factored into (A+B) • (A-B)

Proof : (A+B) • (A-B) =

A2 - AB + BA - B2 =

A2 - AB + AB - B2 =

A2 - B2

Note : AB = BA is the commutative property of multiplication.

Note : - AB + AB equals zero and is therefore eliminated from the expression.

Check : 4 is the square of 2

Check : 121 is the square of 11

Check : a2 is the square of a1

Factorization is : (2a + 11) • (2a - 11)

Final result :

(2a + 11) • (2a - 11)