Let the integer part of root 7 be a and the decimal part be B, and find the value of B (a + root 7)

Let the integer part of root 7 be a and the decimal part be B, and find the value of B (a + root 7)

2 is less than the root, 7 is less than 3
So a = 2, B = (radical 7) - 2
So the original formula = (radical 7-2) (2 + radical 7) [can reverse the square difference formula]
=7-4
=3