Question

is the number (5+✓4) (5-✓4) is irrational or rational Number

Answer 1

it is rational
because on simplifying it we get the final expression to be
25 - 4 =21
By using the identity
A^2 - B^2 = (A+B) * (A-B)

Answer 2

hey mate,, here is ur ans..

⇒( 5 + √4)( 5 - √4)

⇒25 - 5√4 + 5√4 -4

⇒25 - 4

⇒21 ⇒ rational no.

#hope it helps