If the operation X & amp; y is defined as X & amp; y = (x + 2) (y + 1) - 1, then the solution of the equation x & amp; (- 3) = 5 is______ ．

If the operation X & amp; y is defined as X & amp; y = (x + 2) (y + 1) - 1, then the solution of the equation x & amp; (- 3) = 5 is______ ．

According to the meaning of the question: X & amp; (- 3) = - 2 (x + 2) - 1 = 5, remove the brackets: - 2x-4-1 = 5, transfer and merge: - 2x = 10, the solution is: x = - 5

It has been defined: int x = 3, y = 4, z = 5, then the value of the expression! (x + y) + Z-1 & & Y + Z / 2 is, how to find this, want to find the specific solution process

!(x+y)+z-1&&y+z/2
=!(3+4)+5-1&&4+5/2
=!7+5-1&&4+5/2
=0+4&&4+5/2
=4&&6
=1
Priority of operator:
() the highest, down is +, -, *, /, and finally&&
If there is a 0 on the left and right, the result will be 0
4 and 6 are not zero, so the result is 1

5 / 8x + 18 = x + 6 solve the equation

Each term on both sides of the equation is × 8
5x+144=8x+48
The solution is 3x = 144-48
3x=96
X=32
This is called solving the equation without denominator

Sin40 ° = a, then cos40 ° =?

sin²40°+cos²40°=1
That is a & sup2; + cos & sup2; 40 ° = 1
cos²40°=1-a²
cos40°=√1-a²

The known equation x ^ 3 + PX ^ 2 + QX + r = 0 has roots x1, X2, X3 in the complex set. Find the values of X1 ^ 2 + x2 ^ 2 + X3 ^ 2 and X1 ^ 2x2 ^ 2 + X1 ^ 2x3 ^ 2 + x2 ^ 2x3 ^ 2
Please write down the key steps

Because x1, X2 and X3 are three
So (x-x1) (x-x2) (x-x3) = the original formula = 0
The contrast coefficient is X1 + x2 + X3 = - P
x1x2+x2x3+x1x3=q
x1x2x3=r
The back is simple

Given that Tana = 1 / 7, tanb = 1 / 3, and a, B are at (0,90 degrees), try to find the value of a + 2B

[solution] Tana = 1 / 7, tanb = 1 / 3,
So tan2b = 2tanb / [1 - (tanb) ^ 2] = (2 / 3) / (8 / 9) = 3 / 4
So tan (2B + a) = (tan2b + Tana) / (1-tan2btana) = (3 / 4 + 1 / 7) / (25 / 28) = 1
Because a, B are at (0,90 degrees),
So a + 2B = 45 degrees or 225 degrees

Point Q represents - 3 on the number axis, and the distance between another point P and Q on the number axis is five unit lengths. Then what kind of number does the midpoint m of PQ represent?

The distance from point P to q is five unit lengths
The distance between M and Q in PQ is 2.5 unit length,
So the number represented by the midpoint m is - 3-2.5 or - 3 + 2.5,
That is - 5.5 or - 0.5

Given the function f (x) = root 3sinx + acosx + 1, a is a constant, and f (0) = 2, try to express f (x) as asin (Wx + F) + K

F (x) = (under the root sign (9 + A & # 178;) × sin (x + α) + 1, where Tan α = A / 3
Sin α = 3 / (under radical (9 + A & # 178;))
Cos α = A / radical (9 + A & # 178;)
Because f (x) = (under the root sign (9 + A & # 178;) × (SiNx * cos α + cosx * Sina) + 1

A linear equation passing through point a (- 5,2) with an intercept on the x-axis equal to twice the intercept on the y-axis. There are two answers
One is x + 2Y + 1 = 0. The other is 2x + 5Y = 0. Why is there 2x + 5Y = 0?

The intercept of this on both axes is 0
It also meets the double relationship
So it's OK

Use a simple method to calculate the following questions. ① 3.84 * 9.6 + 0.96 * 61.6 ② 2.9 * 0.45 + 0.29 * 4.2 + 0.029 * 13

First:
=3.84*9.6+9.6*6.16
=9.6*(3.84+6.16)
=9.6*10
=96
the second:
=2.9*0.45+2.9*0.42+2.9*0.13
=2.9*（0.45+0.42+0.13）
=2.9*1
=2.9