When a is a, the equation X3 + a = x2 − 16 (x − 12) has innumerable solutions? No solution?

When a is a, the equation X3 + a = x2 − 16 (x − 12) has innumerable solutions? No solution?

From the meaning of the question, we can get: x x = 6a-12, when a = 2, the equation has innumerable solutions; when a ≠ 2, the equation has no solution

What is the value of a when the equation x + a = x 2 / 6 / 1 (x 12) has innumerable solutions?

X / 3 + a = x / 3 + 2
So there are innumerable solutions for a = 2
There is no solution when a is not equal to 2

Six times of x minus one half of 100 is 76. After sphere x subtracts 12 2.5 from a number by equation solution (2), the rest is 50. Find this number (use equation solution x)

1.6X-100*1/2=76
6X=76+50
6X=126
X=21
two
X-12*2.5=50
X=50+30
X=80

-2.25 + [4 times (- 3 / 16) - (7 / 8-0.875)] = ()

=-2.25+(-3/4)-(7/8-7/8)
=-2.25-0.75
=-3

The perimeter of this square lawn is 32 meters. How many square meters is its area?

32 △ 4 = 8M
8 × 8 = 64 square meters

Distinguish DC motor from AC motor
What are the similarities and differences in their basic structures? What are the differences in their working characteristics?

The same: 1. They are all made of the principle that the electrified coil rotates in the magnetic field. 2. They both convert electric energy into mechanical energy. 3. The electricity inside the motor is alternating current
Differences: 1. There is a commutator in the DC motor. 2. The DC motor uses DC or reverses AC to DC, while the AC motor uses AC

If the equation x ^ 3-3x ^ 2-9x + 5 = a has three different real roots, then the value range of a is

f(x)=x^3-3x^2-9x+5-a
F '(x) = 3x ^ 2-6x-9 = 3 (x ^ 2-2x-3) = 3 (x-3) (x + 1) = 0, the extreme point x = - 1,3
The maximum is f (- 1) = - 1-3 + 9 + 5-a = 10-a
The minimum is f (3) = 27-27-27 + 5-a = - 22-a
If there are three different real roots, they are: F (- 1) > 0, f (3) 0, - 22-a

Ten squares with side length of 8 cm are connected as shown in the figure. The connection point is the center of the previous square. The perimeter of the figure is () and the area is ()

The perimeter is (10 * 8 * 2 + 16 = 176) and the area is (28 * 16 = 348)

What's the ratio between time and speed

The formula s = VT tells us that the greater the speed, the shorter the time. So it is obviously inversely proportional

If 3 + 2I is a root of the equation 2x ^ 2 + BX + C = 0, find the value of B and C

Expand (10 + 3B + C) + (24 + 2b) I = 0, then (10 + 3B + C) = 0; (24 + 2b) = 0, B = - 12, C = 26