Question

If a+b=2 ab=4 then the equation whose roots are a, b is

Answer 1

Answer:

x² - 2x + 4 = 0

Step-by-step explanation:

If a and b are roots,

• a + b = 2

=> sum of roots = 2

• ab = 4

=> product of roots = 4

Quadratic equation are written as x² - (sum of roots)x + product of roots = 0

In question, sum = 2 and product is 4.

So,equation is

=> x² - (2)x + 4 = 0

=> x² - 2x + 4 = 0

Answer 2

Answer:

a+b=2

Squaring Both Sides

(a+b)²=(2)²

a²+b²+2ab=4

a²+b²+2(4)=4                         ∴ab=4

a²+b²+8=4

a²+b²=4-8

a²+b²= -4

now let us take roots on both sides

√a²+b²= √-4

a+b= ±2