In VFP, dimension a (3,4) a = 8 A (3,4) = 5 A (3) the output result is a (3) = 8. Why is the result 8 and how to calculate it

In VFP, dimension a (3,4) a = 8 A (3,4) = 5 A (3) the output result is a (3) = 8. Why is the result 8 and how to calculate it

A = 8 & assign 8 to all elements
? a (3) & equivalent to? A (1,3)

In VFP, clear dimension a (3) for n = 1 to 3 s = 4 a (n) = n * 2 + 1 s = S + a (n) endfor s

No problem. Pay attention to the effect of S = 4
When n = 1, a (1) = 3, s = 4 + 3 = 7
When n = 1, s is re assigned to 4, a (2) = 5, and S = 4 + 5 = 9
When n = 1, s is re assigned to 4, a (3) = 7, and S = 4 + 7 = 11
The final output is s = 11

What does the k * * 2 of VFP mean

Is the square of K, and the double star is the power

K! + (K + 1)! +... In VFP M! Inside!
The execution process of the following program is as follows:
clear
Input "please input k value:" to K "
Input "please input m value:" to m "
s=0
for r =k to m
do sub with a,r
s=s+a
endfor
The value of S is, S
return
procedure sub
parameters p,n
p=1
for l=1 to n
p=p*l
endfor
return

It means factorial, not in VFP
For example, 5! = 5 * 4 * 3 * 2 * 1
4!=4*3*2*1
7!=7*6*5*4*3*2*1

Given that the perimeter of a square is x and the area is y, find the functional expression between Y and X

Let the side length of a square be a, then from the meaning that the perimeter of the square is x and the area is y, we can get x = 4A
y=a²②
Solution 1 gives a = x / 4, solution 2 gives a = radical y, a = a, that is, X / 4 = radical y 3
The square of equation 3 is y = x & sup2 / 16
So the function expression between Y and X is y = x & sup2 / 16

If ABC is a different natural number and C of a x B is equal to a (B is not equal to 0), then () a: C is greater than B, B: C is equal to B, C: C is less than B
If it's right,

a=c/ab
c/b=a^2≥0
∴c≥b

2x-4x / 3 plus 9 / 3-2x

[4X/（2X-3）]^2+[9/(3-2X)]=16X^2/[（2X-3）^2]-[9/(2X-3)]=[16X^2-9(2X-3)]/[（2X-3）^2]
=[16X^2-18X+27]/[（2X-3）^2]

Solution equation: 5x + 3 = 3-2x
solve equations:
5x+3=3-2x
3X-2=X+1
Three quarters - 5x = five sixths - two thirds x
Solving linear equation with one variable

7x=0 x=0
4x=3 x=3/4
13/3x=1/12 x=13/36

Given circle C: x ^ 2 + y ^ 2-4x-14y + 45 = 0 and Q (- 2,3). (1) if point P (M.M + 1) is on circle C, find the slope of line PQ
2) If M is any point in a circle, the maximum and minimum of | MQ | are obtained

The equation of circle C is: (X-2) ^ 2 + (Y-7) ^ 2 = 8, which is a circle with (2,7) as the center and 2 times the radius of root sign 2
(1) Dead calculation: take (m, M + 1) into the circular equation, and M = 4
So the point P coordinates are (4,5)
The slope of PQ is one third
(2) If the distance from Q to the center of the circle is 4 times root 2, the maximum value is 4 root 2 + 2 root 2 = 6 root 2
The minimum value is 4 radical 2-2 radical 2 = 2 radical 2
Finished

How does calculator exit from rounding

General calculator as follows
shift+clr
three
=
You can return to the original state
Another calculator has a small hole in the back, which can be poked with a pen