Question

if 1 and -2ar two zeroes of the polynomial (xcube-4x square -7x +10),find its 3rd zero

Answer 1

Answer:

Third Zero is 5.

Step-by-step explanation:

Given:

Polynomial = x³ - 4x² - 7x + 10

Two zeroes are 1 and -2.

To find: Third zero

Given Zeroes are 1 and -2

⇒ Factors from zeroes  = ( x - 1 )  and  ( x + 2 )

We find third factor by dividing given polynomial with product of two obtained factor.

Product of two factors = ( x - 1 )( x + 2 ) = x² + x - 2

On Dividing, we get

Quotient = x - 5

Remainder = 0

Division is attached.

Third factor of the polynomial = x - 5

So, third zero : x - 5 = 0 ⇒ x = 5

Therefore, Third Zero is 5.