Polynomials MCQ: Answers and Explanation

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Jasmine Grover

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The name "polynomial" comes from the words "poly" (meaning many) and "nomial" (meaning phrase), so it means "many terms."

  • A polynomial is made up of solely added, subtracted, and multiplied terms.
  • ax² + bx + c is the form of a quadratic polynomial in x with real coefficients, where a, b, and c are real numbers with a = 0.
  • The degree of a polynomial refers to the variable's highest exponent in the polynomial. 2x² + 4 is an example where the degree is 2.
  • Linear, quadratic, and cubic polynomials have the degrees 1, 2, and 3 polynomials, respectively.
  • A polynomial can have terms with constants such as 5, -2, and others, as well as variables like x and y and exponents such as 2 in y².
  • Addition, subtraction, and multiplication can be used to combine these, but not division.
  • The x-coordinates of the locations where the graph of y = p(x) contacts the x-axis are the zeroes of polynomial p(x).
  • If α and β are the zeroes of the quadratic polynomial ax² + bx + c, then:

Polynomial formula

  • If α, β, γ are the zeroes of the cubic polynomial ax³ + bx² + cx + d = 0, then:

Polynomial formula

  • Zeroes, also known as α, β, γ, follow the rules of algebraic identities, i.e.,

(α + β)² = α² + β² + 2αβ

∴(α² + β²) = (α + β)² – 2αβ

  • If p(x) and g(x) are any two polynomials with g(x) = 0, then p(x) = g(x) * q + r is the division algorithm:

Dividend = Divisor x Quotient + Remainder

The video below explains this:

Polynomials Detailed Video Explanation:


Question 1: If the zeroes of the quadratic polynomial ay² + by + c, c ≠ 0 are equal, then

  1. c and b have opposite signs
  2. c and a have opposite signs
  3. c and b have the same signs
  4. c and a have the same signs

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Answer: (d) c and a have the same signs

Explanation: Discriminant will be equal to zero for equal roots:

b² - 4ac = 0

b² = 4ac

ac = b²/4

ac > 0 (square of any number cannot be negative)

Question 2: If the sum of zeroes of the quadratic polynomial 3x² – kx + 6 is 3, then the value of k is:

  1. 4
  2. 5
  3. 7
  4. 9

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Answer: (d) 9

Explanation: Here a = 3, b = -k, c = 6

Sum of the zeroes, (α + β) = -b/a = 3 …..(given)

⇒ −(−k)/3 = 3

⇒ k = 9

Question 3: The degree of the polynomial, x5 – 2x2 + 2 is:

  1. 2
  2. 4
  3. 1
  4. 5

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Answer: (d) 5

Explanation: In every polynomial, the highest power of the variable is called a degree.

Question 4: If p(x) is a polynomial of degree one and p(y) = 0, then y is said to be:

  1. Zero of p(x)
  2. Value of p(x)
  3. Constant of p(x)
  4. None of the above

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Answer: (a) Zero of p(x)

Explanation: Let p(x) = mx + n

Put x = y

p(y) = my + n = 0

So, y is zero of p(x).

Question 5: A polynomial's zeros can be represented graphically. The number of polynomial zeros equals the number of points on the graph of the polynomial:

  1. Intersects y-axis
  2. Intersects x-axis
  3. Intersects y-axis or x-axis
  4. None of the above

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Answer: (b) Intersects x-axis

Explanation: The number of zeroes of a polynomial is equal to the number of points where the graph of polynomial intersects the x-axis.

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Question 6: A polynomial of degree p has:

  1. Only one zero
  2. At least p zeroes
  3. More than p zeroes
  4. At most p zeroes

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Answer: (d)

Explanation: A polynomial's maximum number of zeroes equals the polynomial's degree.

Question 7: If α and β are the zeroes of a polynomial such that α + β = -6 and αβ = 5, then the polynomial is:

  1. x² + 6x + 5 = 0
  2. x² + 6x - 5 = 0
  3. x² - 6x + 5 = 0
  4. x² - 6x - 5 = 0

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Answer: (a) x² + 6x + 5 = 0

Explanation: Quadratic polynomial is x² – Sx + P = 0, where S is the sum and P is the product

⇒ x² – (-6)x + 5 = 0

⇒ x² + 6x + 5 = 0

Question 8: Zeros of p(x) = x² - 27 are:

  1. ± 3√3
  2. ± 9√3
  3. ± 7√3
  4. None of the above

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Answer: (a)

Explanation: x² - 27 = 0

x² = 27

x = √27

x = ±3√3

Question 9: The quadratic polynomial whose zeroes are 3 + √2 and 3 – √2 is:

  1. x² – 6x - 7
  2. x² + 6x + 7
  3. x² – 6x + 7
  4. x² + 6x - 7

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Answer: (c) x² – 6x + 7

Explanation: S is the sum of zeroes and P is the product of zeroes: 

S = (3 + √2) + (3 – √2) = 6

P = (3 + √2) x (3 – √2) = (3)² – (√2)² = 9 – 2 = 7

So, Quadratic polynomial = x² – Sx + P = x² – 6x + 7

Question 10: If a quadratic polynomial's discriminant, D, is greater than zero, the polynomial has:

  1. two real and equal roots
  2. two real and unequal roots
  3. imaginary roots
  4. no roots

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Answer: (b) two real and unequal roots

Explanation: If the discriminant of a quadratic polynomial, D > 0, then the polynomial has two real and unequal roots.


Also Read:

CBSE X Related Questions

  • 1.
    PQ and PR are two tangents to a circle with centre O and radius 5 cm. AB is another tangent to the circle at C which lies on OP. If \(OP = 13\) cm, then find the length AB and PA.


      • 2.
        A bag contains 25 balls. Some of them are yellow and others are green. One ball is drawn at random. If probability of getting a green ball is \(3/5\), then find the number of yellow balls.


          • 3.
            If the pair of linear equations : \( a_1x + b_1y + c_1 = 0 \) and \( a_2x + b_2y + c_2 = 0 \) is consistent and dependent, then

              • \( \frac{a_1}{a_2} \neq \frac{b_1}{b_2} \)
              • \( \frac{a_1}{a_2} = \frac{b_1}{b_2} = \frac{c_1}{c_2} \)
              • \( \frac{a_1}{a_2} = \frac{b_1}{b_2} \neq \frac{c_1}{c_2} \)
              • \( \frac{a_1}{a_2} = \frac{b_1}{b_2} = \frac{c_1}{c_2} \)

            • 4.
              If \( \alpha, \beta \) are the zeroes of the quadratic polynomial \( px^2 + qx + r \), then find the value of \( \alpha^3\beta + \beta^3\alpha \).


                • 5.
                  If the quadratic equation \(9x^2 + 8kx + 16 = 0\) has real and equal roots, then the value of k is

                    • 3
                    • –3
                    • –4
                    • \(\pm 3\)

                  • 6.
                    There are two sections A and B of Grade X. There are 28 students in Section A and 30 students in Section B. What is the minimum number of books you will acquire for the class library so that they can be distributed equally among students of Section A or Section B ?

                      • 144
                      • 2
                      • 420
                      • 272

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