Find the maximum or minimum value of (x's square + 2x + 1) (x's square + 2x-3) - 6

Find the maximum or minimum value of (x's square + 2x + 1) (x's square + 2x-3) - 6

The original formula = (x + 1) ^ 2 [(x + 1) ^ 2-4] - 6 = (x + 1) ^ 4-4 (x + 1) ^ 2 + 4-10 = [(x + 1) ^ 2-2] ^ 2-10 > = - 10
So the minimum is - 10

-The maximum or minimum of x square + 2x-2

-x²+2x-2
=-(x²-2x)-2
=-(x-1)²-1
There is a maximum
When X-1 = 0, i.e. x = 1
Maximum = - 1

Find the maximum and minimum values of the quadratic function f (x) = 2-2x-3 from zero to three
Big brother and big sister experts, please help me to do it carefully. If I can't do it, I can't go to school. Thank you. Thank you very much!

It should be f (x) = 2x-2x-3. When x = - B / 2A = 1 / 2, the minimum value of the function is - 7 / 2. Because the opening of the parabola is upward, the farther x is from the axis of symmetry, the larger the value of the function is. When x = 3, the maximum value of the function is 9