Ineed to know the sum of -3/5+(-2/3)

-3/5+(-2/3) = 19/15

Step-by-step explanation:

You must make a common denominator for 5 and 3, so you find the least common multiple, 15. then you multiply the denominators by  each other. 3 for the first and 5 for the second.  then you multiply the numerator by the same. Hope this helped.

(n^3 - n)

= n(n-1)(n+1)

since it is divisible by 3 and 2 ,because it is a multiple 3 consecutive number

if, n-1 is odd then n+1 is also odd, then it is a multiple of 9

but if, n-1 is even then n+1 is also even, then it is a multiple of 4

so, largest multiple = max(9*2, 4*3) = max(18, 12) = 18