Question

if a + b = 5 and a b = 2 find (a-b)^2​

Answer 1

Answer:

17

Step-by-step explanation:

according to a algebraic identity

$({a + b}^{2}) \: - \: ( {a - b}^{2}) = 4ab$

()

=>

$( {a - b}^{2}) = ( {a + b}^{2}) - 4ab$

so,

we have

a + b = 5 & ab = 2

so putting these value we get

(a-b) ^2 = (5) ^2 - 4×2

=> (a-b) ^2 = 25 - 8 => 17