Question

Find the value of a if x= -1 is a zero of the polynomial P(x) = 7ax3 +14 ?

Answer 1

Answer:

Step-by-step explanation:

p ( x ) = 7ax³ + 14 = 0

At x = - 1

p ( - 1 ) = 7a ( - 1 )³ + 14 = 0

⇒ 7a ( - 1 ) + 14 = 0

⇒ - 7a + 14 = 0

⇒ 7a = 14

⇒ a = 14/7

⇒ a = 2 is the answer

Answer 2

Given:

polynomial P(x) = 7ax3 +14

To Find:

Find the value of 'a' if x= -1 is a zero of the polynomial

Solution:

A remainder theorem is a theorem that states that if a polynomial P(x) is divided by a linear equation of the form (x-a) then the value P(a) will give the remainder.

Now it is given that x=-1 is the zero of the polynomial P(x) which means if we put the value of x as -1 in the polynomial it will be equal to 0, now

[tex]P(x)=7ax^3+14\\ 0=7a(-1)^3+14\\ 7a=14\\ a=2[/tex]

So the value of the a is 2.

Hence, the value of a is 2.