Factorize each of the following quadratic polynomials by using the method of completing;
a2 + 2a – 3
Coefficient of a2 = 1
Therefore, we have
a2 + 2a – 3 = a2 + 2a + 12 – 12 – 3 (Adding and subtracting 12)
= (a + 1)2 – 22 (Completing the square)
= (a + 1 + 2) (a + 1 – 2)
= (a + 3) (a – 1)
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