y = 1/4x^2 - 10 = 1/4x^2 - 11 = 1/4x^2x^2 = 4x = ±2
y = 3x^2 - 5x0 = 3x^2 - 5x0 = x(3x - 5)x = 0, 5/3
y = x^2 - 6x + 90 = x^2 - 6x + 90 = (x - 3)^2x = 3
y = -x^2 - 4x - 40 = -x^2 - 4x - 40 = x^2 + 4x + 40 = (x + 2)^2x = -2
y = x^2 - 3x - 40 = x^2 - 3x - 40 = (x - 4)(x + 1)x = 4, -1
Таким образом, нули функций:
y = 1/4x^2 - 1
0 = 1/4x^2 - 1
1 = 1/4x^2
x^2 = 4
x = ±2
y = 3x^2 - 5x
0 = 3x^2 - 5x
0 = x(3x - 5)
x = 0, 5/3
y = x^2 - 6x + 9
0 = x^2 - 6x + 9
0 = (x - 3)^2
x = 3
y = -x^2 - 4x - 4
0 = -x^2 - 4x - 4
0 = x^2 + 4x + 4
0 = (x + 2)^2
x = -2
y = x^2 - 3x - 4
0 = x^2 - 3x - 4
0 = (x - 4)(x + 1)
x = 4, -1
Таким образом, нули функций:
x = ±2x = 0, 5/3x = 3x = -2x = 4, -1