Question

What number should be added to polynomial x2 + 2x – 35, so that the 3 is the zero

of polynomial

a) 2 b) – 2 c) 5 d) – 5​

Answer 1

Answer:

The number to be added is 2.

To find:

Find out the number to be added to the given polynomial

Solution:

Let us take f(x)= x^2 -5x+4 and the number which is to be added is assumed to be a.

According to the given problem,

For f(3) to be a zero of the polynomial, a is to be added to the polynomial, that is,

\begin{array} { c } { f ( 3 ) = 3 ^ { 2 } - 5 \times 3 + 4 + a = 0 } \\\\ { 9 - 15 + 4 + a = 0 } \\\\ { 13 - 15 + a = 0 } \\\\ { - 2 + a = 0 } \\\\ { a = 2 } \end{array}

Hence, the number to be added is 2.