Q34 of 40 Page 1

Find the quadratic polynomial, the sum and product of whose zeroes are –3 and 2 respectively. Hence find the zeroes.

The required quadratic polynomial is

x2 – (sum of roots)x + (product of roots) = 0


⇒ x2 + 3x + 2 = 0


[Required polynomial]


⇒ x2 + 2x + x + 2 = 0


⇒ x(x + 2) + 1(x + 2) = 0


⇒ (x + 2)(x + 1) = 0


⇒ x = –2 or –1


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Solve graphically:

2x – 3y + 13 = 0; 3x – 2y + 12 = 0


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From a solid cylinder whose height is 15 cm and the diameter 15 16 cm, a conical cavity of the same height and same diameter is hollowed out. Find the total surface area of remaining solid. (give your answer in terms of π)

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