(n+4)(n-3)-(n+2)(n+5)при n =1/3

1) ( n + 4 )( n - 3 ) = n^2 - 3n + 4n - 12 = n^2 + n - 12 2) - ( n + 2 )( n + 5 ) = - ( n^2 + 5n + 2n + 10 ) = - ( n^2 + 7n + 10 ) = - n^2 - 7n - 10 3) n^2 + n - 12 - n^2 - 7n - 10 = - 6n - 22 4) n = 1/3 - 6 • 1/3 - 22 = - 2 - 22 = - 24