Question

if alpha and beta are zeros of quadratic polynomial x square - 5 x + 6 find the value of alpha + beta minus alpha beta​

Answer 1

Answer:

-1

Step-by-step explanation:

f(x) = x^2 - 5x + 6

Here, a=1, b=-5 and c=6

We know that

alpha+beta=-b/a

alpha+beta=-(-5)/1

alpha+beta= 5

and alpha*beta = c/a

=6/1=6

Now, in alpha+beta - alpha beta

putting the values of alpha+beta and alpha beta,

5 - 6 = -1

Another way is by factorising the polynomial,

x2 -5x +6 = 0

x2 - 2x - 3x + 6 = 0

x(x - 2) -3(x - 2) = 0

(x - 2) (x - 3) =0

now, x - 2 = 0

x = 2 and

x - 3 =0

x = 3

so alpha = 2 and beta = 3

putting the values of alpha and beta in alpha+ beta - alpha beta

2 + 3 - 2*3= 5 - 6 = -1

Hope this will help you

Answer 2

Answer:

-1

Step-by-step explanation:

alpha +beta=(-b/a)=5

alpha×beta=(c/a)=6

(alpha+beta)-(alpha×beta)=(5-6)=-1