Q20 of 39 Page 91

If α and β are zeros of quadratic polynomial x2 – 5x + 6 then find the value of α2 + β2.

As the sum of roots = 5


⇒ α + β = 5


Also, the product of roots = 6


⇒ α×β = 6


So, α2 + β2 = (α + β)2 – 2α×β


= 52 – 12


= 25 – 12


= 13


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