Q25 of 39 Page 91

If α and β are the zeroes of the quadratic polynomial p(x) = ax2 + bx + c then evaluate α – β.

Given: p(x) = ax2 + bx + c

sum of roots = α + β =


product of roots = α × β =


So, (α – β)2 = α2 + β2 – 2×α×β


= α2 + β2 + 2×α×β – 2×α×β


= (α + β)2 – 4×α×β








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