Q1 of 227 Page 82

Find the zeros of the following quadratic polynomials and verify the basic relationships between the zeros and the coefficients.

4x2 + 8x

Let f(x) = 4x2 + 8x

Arranging equation in proper form.


Now, f(x) = 4x2 + 8x + 0


To find out zeros of the given polynomial.


We put f(x) = 0


f(x) = 4x2 + 8x + 0 = 0


4x2 + 8x = 0


4x(x + 2) = 0


Now, 4x = 0


x = 0


When, (x + 2) = 0


Then, x = – 2


Our zeros are α = 0 and β = – 2.


sum of zeros = α + β = 0 + ( – 2)


sum of zeros = α + β = – 2.


Product of zeros = αβ = 0 × ( – 2) = 0.


Now, Comparing f(x) = 4x2 + 8x + 0 with standard equation ax2 + bx + c.


We get, a = 4, b = 8 and c = 0.


We can verify,


Sum of zeros =


i.e. α + β =


α + β = – 2


Product of zeros =


αβ =


Hence, relationship between zeros and coefficient is verified.


More from this chapter

All 227 →