On dividing x3 – 3x2 + x + 2 by a polynomial g(x), the quotient and remainder were x – 2 nd –2x + 4, respectively. Find g(x).
Given ,
Dividend p(x) = x3 - 3x2 + x + 2
Quotient = x – 2
Remainder = -2x + 4
Let divisor = g(x)
As we know ,
Dividend = Divisor × Quotient + Remainder
x3- 3x2 +x+ 2 = g(x) × (x – 2) + (-2x + 4)
x 3- 3x2 + x + 2 – (-2x + 4) = g(x) × (x – 2 )
Therefore, g(x) × (x – 2 ) = x3 – x2 + x + 2
Now we will divide p(x) by quotient x – 2 to find divisor g(x)
Therefore , g(x) = ( x2 – x + 1 )
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(i) x2 – 2x – 8 (ii) 4s2 – 4s + 1 (iii) 6x2 – 3 – 7x (iv) 4u2 + 8u (v) t2 – 15 (vi) 3x2 – x – 4
Find a quadratic polynomial each with the given numbers as the sum and product of its zeroes respectively.
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(i) t2 – 3, 2t4 + 3t3 – 2t2 – 9t – 12
(ii) x2 + 3x + 1, 3x4 + 5x3 – 7x2 + 2x + 2
(iii) x3 – 3x + 1, x5 – 4x3 + x2 + 3x + 1
Find a cubic polynomial with the sum, sum of the product of its zeroes taken two at a time, and the product of its zeroes as 2, –7, –14 respectively.
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Divide the polynomial p(x) by the polynomial g(x) and find the quotient and remainder in each of the following :
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If the polynomial x4 – 6x3 + 16x2 – 25x + 10 is divided by another polynomial x2 – 2x + k, the remainder comes out to be x + a, find k and a.
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(i) Probability of an event E + Probability of the event ‘not E’ = .
(ii) The probability of an event that cannot happen is . Such an event is called .
(iii) The probability of an event that is certain to happen is . Such an event is called .
(iv) The sum of the probabilities of all the elementary events of an experiment is .
(v) The probability of an event is greater than or equal to and less than or equal to .
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(ii) A player attempts to shoot a basketball. She/he shoots or misses the shot.
(iii) A trial is made to answer a true-false question. The answer is right or wrong.
(iv) A baby is born. It is a boy or a girl.
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(C) 70° (D) 80°
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