Some Math Problems

1. Subtract and simplify.    (-8+5i)-(-5-8i)

2. Simplify.      (-i)⁶

3.  Determine the nature of the solutions of the equation.       x² - x + 8 = 0

4. Multiply and simplify the following expression.      [x - (5+9i)] [x - (5-9i)]

5.  Use the quadratic formula to find the exact solutions of the following equation.      x² + 6x + 4 = 0

6. Solve.     x-9√x + 8 = 0

7. For the function f(x) = -8x² -40x + 3. find the vertex, determine whether there is a maximum value and find that value, find the range, and find the intervals on which the function is increasing and decreasing.

8. Solve.    √x+49 = x-7

9. Solve  1/A = 1/s + 1/t   for t.