Use the remainder theorem to verify this statement. (x+5) is a factor of the function f(x)= x^3+3x^2-25x-75. Find the (blank) of f(x) and x+5. The (blank) of this operation is 0. Therefore, (x+5) is (blank) of function f. So f(blank) =0. Blank choices:
1. product, sum, difference, or quotient
2. sum, discriminant, quotient, or remainder
3. the opposite, the simplified form, not a factor, a factor
4. -5, -75, 75, 5