\(i:=0;\ while\left(i<10\right)\ i++;\)
Sau đoạn ct, \(i\) có giá trị bao nhiêu?
#include <bits/stdc++.h>
using namespace std;
long long a[1000000],n,s=0,d=0;
int main()
{
cin>>n;
for(int i=0;i<n;i++)
{
cin>>a[i];
}
for(int i=0;i<n;i++)
{
if(a[i]%2==0)
s+=a[i];
else
if(a[i]%2==1)
d+=a[i];
}
cout<<s<<endl;
cout<<d;
}
x=4x=4 là nghiệm của những phương trình nào dưới đây?
\frac{x^2-6x+8}{x^2-9x+20}=0x2−9x+20x2−6x+8=0 \frac{4x-16+\left(8-2x\right)}{x^2+16}=0x2+164x−16+(8−2x)=0 \frac{x^2-16}{x^3+16}=0x3+16x2−16=0 \frac{x^3-64}{x^2-16}=0x2−16x3−64=0Olm chào em. Cảm ơn em đã dùng nền tảng olm cho việc học tập và giao lưu với cộng đồng tri thức. Đây không phải là toán lớp 4. Vì vậy em cần đăng đúng môn học.
3cotx-2=0
3tanx+4=0
6sinx-3=0
4cotx+2=0
cotx-1=0
sin(x+ \(\frac{\pi}{2}\))=1
sin 3x=0
ĐKXĐ: ...
a/ \(cotx=\frac{2}{3}\Leftrightarrow x=arccot\left(\frac{2}{3}\right)+k\pi\)
b/ \(tanx=-\frac{4}{3}\Leftrightarrow x=arctan\left(-\frac{4}{3}\right)+k\pi\)
c/ \(sinx=\frac{1}{2}\Leftrightarrow\left[{}\begin{matrix}x=\frac{\pi}{6}+k2\pi\\x=\frac{5\pi}{6}+k2\pi\end{matrix}\right.\)
d/ \(cotx=-\frac{1}{2}\Leftrightarrow x=arccot\left(-\frac{1}{2}\right)+k\pi\)
e/ \(cotx=1\Leftrightarrow x=\frac{\pi}{4}+k\pi\)
f/ \(sin\left(x+\frac{\pi}{2}\right)=1\Leftrightarrow x+\frac{\pi}{2}=\frac{\pi}{2}+k2\pi\Leftrightarrow x=k2\pi\)
g/ \(3x=k\pi\Leftrightarrow x=\frac{k\pi}{3}\)
I/ Choose the best answer:
1. Choose the word which is pronounced differently from the others:
A. wanted |
B. worked |
C. needed |
D.visited |
2. Choose the word which has different stress from the others:
A. lacquerware |
B. pottery |
C. embroider |
D.layer |
3. He works as an ___________ in his uncle’s workshop.
A. attraction |
B. artisan |
C. embroider |
D.lacquer |
4. They need to find a solution to ___________ the local environment.
A. preserve |
B. cast |
C. weave |
D.knit |
5. The company is going to close ___________ one of its stores due to reduced sales.
A. on |
B. down |
C. in |
D.at |
6. He was hired for the position because he is ___________.
A. reliability |
B. reliably |
C. reliable |
D.unreliable |
7. I love going to this place _____________ it’s the quietest place in the city.
A. so |
B. though |
C. so that |
D.as |
8. Nothing is __________ than being stuck in a traffic jam.
A. worse |
B. badly |
C. more badly |
D.the worst |
9. When I __________, the town hall was already full of teenagers.
A. turned on |
B. turned off |
C. turned up |
D.turned into |
10. Nam: There’s a lantern festival nearby. Do you want to come with us?
Mai: Yeah, ___________ !
A. sorry |
B. cool |
C. I see |
D.not at all |
11. Remember to _________ your shoes when you enter a Japanese house.
A. take over |
B. take on |
C. take up |
D.take off |
12. The roads are ___________ as one of the solutions to deal with traffic jams.
A. extended |
B. expensive |
C. overcrowding |
D.shelter |
I/ Choose the best answer:
1. Choose the word which is pronounced differently from the others:
A. wanted |
B. worked |
C. needed |
D.visited |
2. Choose the word which has different stress from the others:
A. lacquerware |
B. pottery |
C. embroider |
D.layer |
3. He works as an ___________ in his uncle’s workshop.
A. attraction |
B. artisan |
C. embroider |
D.lacquer |
4. They need to find a solution to ___________ the local environment.
A. preserve |
B. cast |
C. weave |
D.knit |
5. The company is going to close ___________ one of its stores due to reduced sales.
A. on |
B. down |
C. in |
D.at |
6. He was hired for the position because he is ___________.
A. reliability |
B. reliably |
C. reliable |
D.unreliable |
7. I love going to this place _____________ it’s the quietest place in the city.
A. so |
B. though |
C. so that |
D.as |
8. Nothing is __________ than being stuck in a traffic jam.
A. worse |
B. badly |
C. more badly |
D.the worst |
9. When I __________, the town hall was already full of teenagers.
A. turned on |
B. turned off |
C. turned up |
D.turned into |
10. Nam: There’s a lantern festival nearby. Do you want to come with us?
Mai: Yeah, ___________ !
A. sorry |
B. cool |
C. I see |
D.not at all |
11. Remember to _________ your shoes when you enter a Japanese house.
A. take over |
B. take on |
C. take up |
D.take off |
12. The roads are ___________ as one of the solutions to deal with traffic jams.
A. extended |
B. expensive |
C. overcrowding |
D.shelter |
I/ Choose the letter (A, B, C or D) that indicates the best answer to each of the following questions. Write your answers in the box provided.
1. Choose the word which is pronounced differently from the others:
A. proofs |
B. books |
C. points |
D.days |
2. Choose the word which has a different stress from the others:
A. pollute |
B. deny |
C. happen |
D. occur |
3. Choose the word which is pronounced differently from the others:
A. meal |
B. tea |
C. meat |
D.bread |
4. Mary often goes to the supermarket ____________ Sundays.
A. in |
B. at |
C. from |
D.on |
5. _________ it was so cold, he went out without an overcoat.
A. Although |
B. Because |
C. As |
D.If |
6. Tom said that he _________in Leeds in England.
A. is living |
B. lived |
C. were living |
D.has lived |
7. ___________ does it take you to your hometown? – About 30 minutes.
A. How often |
B. How far |
C. How long |
D.How many |
8. Lan ________the train if she is not in a hurry.
A. will miss |
B. misses |
C. missed |
D.will not miss |
9. His salary isn’t enough for his family to live _____________.
A. at |
B. about |
C. on |
D.into |
10. Karachi in Pakistan is the second __________ city in the world in population.
A. large |
B. larger |
C. more large |
D.largest |
11. When he was young, he ___________go fishing with his father.
A. used |
B. uses |
C. used to |
D.is using |
12. Mai: “Thank you very much for helping me!” – Nam: “ _____________.”
A. Not at all |
B. Good idea |
C. Sorry |
D.Cool |
13. She helped me to ____________ my son while I was away.
A. take over |
B. look after |
C. look at |
D.get off |
14. The traffic is so heavy. I wish there ________ fewer cars.
A. are |
B. were |
C. will be |
D.have been |
15. The children felt __________when their mother was coming back home.
A. excitement |
B. excitedly |
C. excited |
D.exciting |
I.
1D. days
2C. happen
3D. bread
4D. on
5A. although
6D. has lived
7C. how long
8A. will miss
9C. on
10D. largest
11C. used to
12A. Not at all
13B. look after
14B. were
15C. Excited
Giải các phương trình tích sau :
a, 4x2 - 12x +9 = 0
b, 3x2 + 7x + 2 = 0
c, x2 - 4x + 1 = 0
d, 2x2 - 6x + 1 = 0
e, 3x2 + 4x - 4 = 0
#include<bits/stdc++.h>
using namespace std;
int main()
{
int n;
cin>>n;
int A[n],B[n],C[2*n];
for (int i=0; i<n;i++)
{
cin>>A[i];
}
for (int i=0;i<n; i++)
{
cin>>B[i];
}
for (int i=0;i<n;i++)
{
C[2*i]=A[i];
C[2*i+1]=B[i];
}
for (int i=0; i<2*n;i++)
{
cout<<C[i]<< " ";
}
}
#include <iostream>
using namespace std;
int main()
{
int n, x;
cin >> n;
int a[n];
for (int i = 0; i < n; i++)
cin >> a[i];
int q;
cin >> q;
while (q--)
{
int cnt = 0;
cin >> x;
for (int i = 0; i < n; i++)
if (a[i] == x)
cnt++;
cout << cnt << endl;
}
return 0;
}
#include <bits/stdc++.h>
using namespace std;
long long n, a[100000], i, b[100000], s, j, k;
int main()
{
cin >> n;
for (i = 1; i <= n; i++)
{
cin >> a[i];
}
k = 2;
b[1] = 0;
for (i = 2; i <= n; i++)
{
for (j = 1; j <= i - 1; j++)
{
if (a[j] > a[i])
{
s++;
}
}
b[k] = s;
k++;
s = 0;
}
for (i = 1; i <= k - 1; i++)
{
cout << b[i] << " ";
}
}
a) x (x+3)=0
b)(x-2)(5-x)=0
c)(x-1)(x2+1)=0
a, x(x+3)=0
=>x hoặc x+3=0
=>x+3=0
=>x=0-3
=>x=-3
=>x= 0 hoặc x=-3
b, (x-2)(5-x)=0
=>x-2 hoặc 5-x=0
=>x= 0+2 hoặc x= 5-0
=>x= 2 hoặc x= 5
c, (x-1)(x2+1)=0
=>x-1 hoặc x2-1=0
=>x=1 ->(1)
x2-1=0
=>x2=1
=>x=1
Vậy x=1
a) x(x+3)=0
=>x=0 hoặc x+3=0
x=-3
Vậy x=0; x=-3
b)(x-2)(5-x)=0
=>x-2=0 hoặc 5-x=0
x=2 x=5
Vậy x=2; x=5
c)(x-1)(x2+1)=0
=>x-1=0 hoặc x2+1=0
x=1 x2=-1(vô lí)
Vậy x=1
a)\(x\left(x+3\right)=0\)
\(\Leftrightarrow\left[\begin{array}{nghiempt}x=0\\x+3=0\end{array}\right.\)\(\Leftrightarrow\left[\begin{array}{nghiempt}x=0\\x=-3\end{array}\right.\)
b)\(\left(x-2\right)\left(5-x\right)=0\)
\(\Leftrightarrow\left[\begin{array}{nghiempt}x-2=0\\5-x=0\end{array}\right.\)\(\Leftrightarrow\left[\begin{array}{nghiempt}x=2\\x=5\end{array}\right.\)
c)\(\left(x-1\right)\left(x^2+1\right)=0\)
\(\Leftrightarrow x-1=0\) (vì \(x^2+1>0\))
\(\Leftrightarrow x=1\)