12.56 * 1 / 3 is equal to?

12.56 * 1 / 3 is equal to?

Approximately equal to 4.19

How to change the image of y = SiNx to get y = SiNx + sin (x + Pie / 3)

Y = SiNx + sin [x + (π / 3)] = SiNx + (1 / 2) SiNx + (√ 3) cosx / 2 = (3sinx / 2) + [(√ 3) cosx / 2] = (√ 3) sin [x + (π / 6)] y = SiNx - > y = (√ 3) sin [x + (π / 6)] there are two methods: 1) change x first, then change y; 2) change y first, then change X. according to different methods, the order is 1) shift π / 6 to the left, and then

How much is eleven times eleven

If this is an arithmetic question, the answer should be 121 (= 11 x 11)
If this is a language problem, the answer should be very soil (= soil by soil = Double soil)
If this is a political issue, the answer should be prosperity of the national day
If this is a lantern riddle, the answer should be plenty of food and clothing
If this is a religious issue, the answer should be that it is difficult to enter the narrow gate. (according to the Bible, among the ten lepers who have been cured, only one came back to thank Jesus
Write a lot of answers, already very tired. Please, please, give points

If TaNx = 2, then tan2 (x-45 °) =?

This is a basic question,
tan(x-45°）=（tanx-1)/(1+tanx tan45°）=1/3
tan2(x-45°）=2tan(x-45°）/(1-tan²（x-45°））=3/4
If the calculation is OK, the problem is right. At least the idea is right
study hard and make progress every day!

0.279 × 355 + 0.645 × 279 are calculated by simple method

0.279×355+0.645×279
=0.279×355+645×0.279
=0.279×（355+645）
=0.279×1000
=279

Ellipse e: a = 8, B2 = 4, the focus is on the x-axis. Let Q (1,0) pass through the q-point and lead a straight line L to the intersection of ellipse E and AB to find the trajectory equation of the midpoint P of line ab

Let a (x1, Y1) B (X2, Y2) P (x, y)
P is the midpoint of AB, then X1 + x2 = 2x, Y1 + y2 = 2Y
Elliptic equation x & # 178 / 8 + Y & # 178 / 4 = 1
x1²/8+y1²/4=1
x2²/8+y2²/4=1
The two formulas are subtracted to get the
(x1+x2)(x1-x2)/8=-(y1+y2)(y1-y2)/4
⇒(y1-y2)/(x1-x2)=-(x1+x2)/2(y1+y2)
On the left is the slope k of the straight line AB, and on the right it is replaced by Formula 1
We get k = - X / 2Y
In addition, AB over Q (1,0) P (x, y)
So the slope k = Y / (x-1) 3
It can be obtained from (2) and (3)
-x/2y=y/(x-1)
⇒2y²=-x²+x
⇒x²+2y²-x=0
This is the trajectory equation of point P
In addition, q (1,0) is inside the ellipse, so it is not necessary to discuss the range of slope

2X + 3 ＞ 3x, the sum of integer solutions of 3% x + 3 minus 6% X-1 is greater than 2% 1

2X + 3 > 3x solution leads to x = 1 / 2 solution leads to x > = - 4
So the sum of integers is - 4 + - 3 + - 2 + - 1 + 0 + 1 + 2 = - 7

Why does the equation ax2-2x-1 = 0 have real roots when a is a? And find out its real number root

When a = 0, the original equation is a quadratic equation of one variable, and its deformation is - 2x-1 = 0, the solution is x = - 12; when a ≠ 0, the original equation is a quadratic equation of one variable, and △ ≥ 0, the equation has a real root, that is, 22-4 × a × (- 1) ≥ 0, the solution is a ≥ - 1 and a ≠ 0, x = 2 ± 4 + 4a2a, that is, X1 = 1 + 1 + AA, X2 = 1 − 1 + AA, so a = 0, the solution is x = - 12; when a ≥ - 1 and a ≠ 0, the solution is X1 = 1 + 1 + AA, X2 = 1 − 1+ aa．

How can 3.2 * 0.125 * 25 be easily calculated?

3.2*0.125*25
=8*0.125*0.4*25
=1*10
=10

If point P is on the curve X ^ 2 + 4 * y ^ 2 = 4 and the distance to the straight line y = 2 is 1, then the coordinate of point P is

Curve X ^ 2 / 4 + y ^ 2 = 1
Then a = 2, B = 1
It's an ellipse
The distance from the top vertex (0,1) of the imaginary axis to y = 2 is 1
The coordinates of point P are (0,1)