Question

If 2 is a root of the equations ay2 + ay + 3 = 0 and y2 + y + b = 0, then find the
value of ab.

Answer 1

Answer:

ay

2

+ay+3=0

as 1 is root then

⇒a(1)

2

+a(1)+3=0

⇒a+a=−3

⇒2a=−3

⇒a=−

2

3

y

2

+y+b=0

⇒(1)

2

+1+b=0

⇒2+b=0

⇒b=−2

∴ab=−

2

3

×−2=3