There are 50 students in class 61, including 26 boys and 24 girls. The ratio of the number of girls to the number of the whole class is 1

The ratio of the number of female students to the number of the whole class = 24:50 = 12:25

There are 50 students in class 61. Girls account for two fifths of the class. How many girls and boys are there

There are 20 women and 30 men

There are 5 "three good" students in class 6 (1), accounting for 1 / 9 of the class. There are () students in the class

5÷1/9
forty-five

As shown in the figure, the area of an isosceles right triangle is 4 square centimeters, and the vertex o of the triangle is at the center of the circle?
Lie equation, but also solve the equation.

Let the radius be r, that is, the right side of an isosceles right triangle be r
r²/2=4
The area of a circle s = R & # 178; π = (2 √ 2) &# 178; π = 8 π

Let F 1 and F 2 be the two focal points of hyperbola a with X-Y = 1, if f 1F 2p [0,2b] is an equilateral triangle

f1f2=2c
If the triangle f1f2p is a regular triangle
So the angle f1po is 30 degrees
In the right triangle f1op
tan30=of1/op
√3/3=c/2b
1/3=c²/4b²
b²=3c²/4
a²+b²=c²
a²+3c²/4=c²
a²=1/4c²
c²/a²=4
c/a=2
e=2
The centrifugation is 2

It is proved that the results of second order mixed derivatives are independent of the order of derivation if and only if the mixed derivatives are continuous in the domain of definition

The continuity of the mixed derivative in the domain of definition is only a sufficient condition, not a necessary condition, that the result of the second mixed derivative is independent of the order of derivation

Divide 6 boxes of apples into 7 classes averagely, and each class is divided into () boxes of apples. A.1/7 b.6/7 c.1/6

1. The symmetry axis of the image of quadratic function y = (x-1) &# - 2 is a straight line___ .
2. If the parabola y = x & # 178; + BX + 4 is shifted 3 units to the right and 2 units to the down, the analytic expression of the image obtained is y = x & # 178; - 2x-1, then the value of B is .
3. The vertex of parabola y = 2x & # 178; - 8x + 2 = 0 is C. given that the image of y = - KX + 3 passes through point C, then the area of the triangle formed by the image of this first-order function and the two coordinate axes is_ .

x=1
four
one

If f (x) = (- xsquare + 1) / (xsquare-2), is f (x) odd or even? What is the domain of F (half x) = 2?
What is the solution of F (half x) = 2

1, f (x) is even function. 2, X is equal to (plus or minus 20 / 3) square root

There are 50 students in class 61, including 26 boys and 24 girls. The ratio of the number of girls to the number of the whole class is 1