Question

if x=4 y=3 then( x2-y2) (x2+y2)=2

Answer 1

x = 4 and y = 3

so, (x²-y²(x²+y²) = (4² - 3²)(4² + 3²) 
     = (16 -9 )(16+9)
     = (7)(25) = 175