Question

if a and b are the zeroes of x^2 +x-2 ..find vaue of 1/a - 1/b

Answer 1

Given equation :

x² + x - 2

Using middle term factorisation –

= x² + 2x - x - 2

= x ( x + 2 ) - 1 ( x + 2 )

= ( x + 2 ) ( x - 1 )

To find the zeroes, we have to put equals to 0 using Zero - Product Rule.

So,

x + 2 = 0 and x - 1 = 0

x = - 2 and x = 1

It is given in the question that a and b are the zeroes.

•°•

a = - 2 and b = 1

Now,

( 1 / a ) + ( 1 / b )

= ( 1 / - 2 ) + ( 1 / 1 )

= ( - 1 / 2 ) + ( 1 / 1 )

LCM of 2 and 1 = 2

= ( - 1 + 2 ) / 2

= 1 / 2

= 0.5

$\large\star$ $\large\bold\red{TheSia}$ $\large\star$

Answer 2

complete equation is needed to solve this6 ques. I assume x^2 +x - 2 = 0 is the complete equation.
if a and b be the zeroes then
a+b = -1/1=-1
ab =-2/1= -2
now (a-b)^2=(a+b)^2-4ab =(-1)^2-4×-2=1+8=9
therefore (a-b)=3 or -3
now 1/a-1/b=-(a-b)/ab =-3/-2 or 3/-2
therefore 1/a-1/b =3/2 or -3/2.
hope it helps. please mark this answer as brainliest if it helped.