⇒2A>1√1+√2+1√2+√3+1√3+√4+1√4+√5+...+1√2024+√2025⇒2A>11+2+12+3+13+4+14+5+...+12024+2025
⇒2A>√2−√1+√3−√2+√4−√3+...+√2025−√2024⇒2A>2−1+3−2+4−3+...+2025−2024
⇒2A>√2025−√1=44⇒2A>2025−1=44
⇒A>22⇒A>22
⇒2A>1√1+√2+1√2+√3+1√3+√4+1√4+√5+...+1√2024+√2025⇒2A>11+2+12+3+13+4+14+5+...+12024+2025
⇒2A>√2−√1+√3−√2+√4−√3+...+√2025−√2024⇒2A>2−1+3−2+4−3+...+2025−2024
⇒2A>√2025−√1=44⇒2A>2025−1=44
⇒A>22⇒A>22
1-2+3-4+5-6+7-8+...+2023-2024
1) Tính hợp lý :
P=1-2-3+4+5-6-7+8+.........+2021-2022-2023+2024
Tính:1 - 2 - 3 + 4 + 5 - 6 - 7 + 8 + 9 - 10 - 11 +...-2023+2024+2025 mình cần gấp ạ
Tìm số nguyên dương x sao cho 5x +13 là bội của 2x+1
Tìm x biết (2x-18).(3x+12)=0
Tính S= 1-2-3+4+
5-6-7+8+...+2021-2022-2023+2024+2025
cho a =1/3 - 2/3*2 + 3/3*3 - 4/3*4 + 5/3*5 - ...... + 2023/3*2023 - 2024/3*2024 hãy so sánh a với 20/3
CMR1×2-1/2!+2×3-1/2!+3×4-1/4!+...+2023×2024/2024!<2
A = \(\dfrac{1}{3}\)-\(\dfrac{2}{^{ }3^2}\)+\(\dfrac{3}{3^3}\)-\(\dfrac{4}{3^4}\)+...+\(\dfrac{2023}{3^{2023}}\)-\(\dfrac{2024}{3^{2024}}\) so sánh A với \(\dfrac{3}{16}\)
Tìm x thuộc Z, biết:
a, 8x . ( 2023 + x ) - 8x . ( x + 2024 ) = 56
b, 5 - 2025x = 9 - 2026 . ( x - 1 )
c, ( - 12 ) mũ 2 . x = 56 + 10 . 13x
d, - ( x - 32 + 11 ) = ( 21 - 33 - x + 7 )
e, - 2 . ( x + 6 ) + 6 . ( x + 10 ) = 8
Tính nhanh: \(\dfrac{7}{1`2}.\dfrac{2024}{2023}-\dfrac{7}{2023}.\dfrac{1}{2}\)