x
2
+
y
2
=
16
...
...
...
...
...
...
.
.
(
1
)
x + y = 4 (2)
rearrange (2) to y = 4 - x (could do x = 4 - y )
substitute y = 4 - x into (1)
hence:
x
2
+
(
4
−
x
)
2
=
16
⇒
x
2
+
16
−
8
x
+
x
2
=
16
and
2
x
2
−
8
x
+
16
−
16
=
0
⇒
2
x
2
−
8
x
=
0
factor and solve : 2x(x - 4 ) = 0
⇒
x
=
0
,
x
=
4
substitute these values into y = 4 - x , to find corresponding values of y.
x = 0 : y = 4 - 0 = 4 → (0 , 4)
x = 4 : y = 4 - 4 = 0 → (4 , 0 )
These are the points of intersection with the line x +y = 4 and the circle
x
2
+
y
2
=
16
Answer link
Объяснение:
Var
N,A:integer;
Begin
Write('N = ');Read(N);
A:=0;
While N>0 do
Begin
if (N mod 10) > A then A:= N mod 10;
N:=N div 10;
End;
Write(A)
End.
Var
N,A,B:integer;
C:boolean;
Begin
Write('N = ');Read(N);
A:=-1;
B:=-2;
C:=false;
While N>0 do
Begin
if A=B then C:=true;
if N>0 then
Begin
A:=N mod 10;
N:=N div 10;
End;
if A=B then C:=true;
if N>0 then
Begin
B:=N mod 10;
N:=N div 10;
End;
End;
if A=B then C:=true;
if C then Write('Есть')
else Write('Нет')
End.
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