If SiNx = 4 / 5 and X is an acute angle, then SiNx / 2-cosx / 2=

If SiNx = 4 / 5 and X is an acute angle, then SiNx / 2-cosx / 2=

(sinx/2-cosx/2)²=(sinx/2)²+(cosx/2)²+2*sinx/2*cosx/2=1+2*sinx/2*cosx/2=1+sinx=9/5
X is an acute angle
x/2

900 △ 38 = simple calculation

38=2 ×19
So 900 △ 38 = 450 out of 19

Let f be the left focus of 2 / 2 x square + y square = 1. Let a straight line passing through point F intersect an ellipse at AB, and the midpoint m of line AB is at x = - Y. then the equation of AB is solved
(2) The equation of circle n passing through point o.f and tangent to left quasilinear l of ellipse

Let f be the left focus of 2 / 2 x square + y square = 1. Let a straight line passing through point F intersect an ellipse at AB, and the midpoint m of line AB is at x = - Y. then the equation of AB is solved
a^2=2,b^2=1,c^2=2-1=1
So the left focus f (- 1,0), let the AB equation be y = K (x + 1), and substitute it into the ellipse:
x^2/2+k^2(x+1)^2=1
(1/2+k^2)x^2+2k^2x+k^2-1=0
x1+x2=-2k^2/(1/2+k^2)
y1+y2=k(x+x2+2)=k(-2k^2/(1/2+k^2)+2)
The midpoint of AB is y + x = 0, that is, (Y1 + Y2) / 2 + (x1 + x2) / 2 = 0
It can be substituted into the calculation to get K

Because 24 divided by 6 equals 4, 24 is a multiple and 6 is a factor. Right or wrong?

It's wrong
Multiples and factors are relative. 24 is a multiple of 6 and 6 is a factor of 24. We can't say who is a factor and who is a multiple alone

If both of the equations x2-2ax + 4 = 0 are greater than 1, then the value range of the real number a is?

By using Veda's theorem, let two of the equations x2-2ax + 4 = 0 be X1 and x2
Then (x1 &; 1) (x2 &; 1) > 0.4 &; 2A + 1 > 0
(x1−1)+(x2−1)＞2 ∴ 2a−2＞2
△≥0 4a^2−16≥0
The solution is 2 ≤ a < 5 / 2

If you divide a decimal by 0.01, you will enlarge the decimal to 100 times the original______ (judge right or wrong)

If you divide a decimal by 0.01, you will enlarge the decimal to 100 times the original

(1)3x-27=-3X+5 (2)12-3(2-y)=6y+5

(1)
3x - 27 = -3x + 5
3x + 3x = 5 + 27
6x = 32
x = 32 ÷ 6
x = 16/3
(2)
12 - 3(2 - y) = 6y + 5
12 - 6 + 3y = 6y + 5
6y - 3y = 12 - 6 - 5
3y = 1
y = 1/3

Divide the nine numbers 20, 26, 33, 35, 39, 42, 44, 55 and 91 into three groups to make the product of each group equal

20 = 2 × 2 × 526 = 2 × 1333 = 3 × 1135 = 5 × 739 = 3 × 1342 = 2 × 3 × 744 = 2 × 2 × 1155 = 5 × 1191 = 7 × 13, there are six 2, three 3, 5, 7, 11, 13 in it. Therefore, if 20, 44, (26, 42) are separated first, then 26, 42 and 55 are exactly one group; if we look at 20, 33, 91, then 35, 44, 39 are left. That is 26 × 42 × 55 = 20 × 33 × 91 = 35 × 39 × 44

If 2x-5y + 2 = 0, try to find 4 ^ x times 1 / (32 ^ y)

2x-5y+2=0,
2x-5y=-2
4 ^ x times 1 / (32 ^ y)
=2^2x×1/2^(-5y)
=2^(2x-5y)
=2^(-2)
=1/4

X minus 0.36 x equals 16

x-0.36x=16
0.64x=16
x=16÷0.64
x=25