Tinh nhanh:
(-1)*(-1)^2*(-1)^3*(-1)^4*...*(-1)^99*(-1)^100
Giup minh nhe!
(1/2-1):(1/3-1):(1/4-1):...:(1/98-1):(1/99-1):(1/100-1)
Tinh nhanh nhanh nhe
= -1/2.(-2/3).(-3/4). .... .(-99/100)
= -(1/2.2/3. .... . 99/100)
= -(1.2.3. .... . 99/2.3.4. .... . 100)
= -1/100
Tk mk nha
Tinh nhanh:
m)5^1+5^2+5^3+...+5^199+5^200
n)3^0-3^2+3^3-3^4+...+3^2017-3^2018+3^2019-3^2020
o)6+6*9+6*9^2+6*9^3+...+6*9^99
p)(-1)*(-1^2)*(-1^3)*(-1^4)*...*(-1^99)*-(1^100)
Giup minh nhe!
Đặt \(A=5+5^2+5^3+....+5^{199}+5^{200}\)
\(\Leftrightarrow5A=5\left(5+5^2+5^3+....+5^{199}+5^{200}\right)\)
\(\Leftrightarrow5A=5^2+5^3+5^4+....+5^{200}+5^{201}\)
\(\Leftrightarrow5A-A=\left(5^2+5^3+5^4+....+5^{200}+5^{201}\right)-\left(5+5^2+5^3+....+5^{199}+5^{200}\right)\)
\(\Leftrightarrow4A=5^{201}-5\)
\(\Leftrightarrow A=\frac{5^{201}-5}{4}\)
Tinh nhanh
1/2 +3/5 + 1/9 + 1/127 + 7/ 18 + 4/35+ 2/7
ai dung minh tick cho nhe . Minh can gap nhe
1/2+3/5+1/9+1/127+7/18+4/35+2/7
=(1/2+1/9)+(3/5+2/7)+1/127+7/18+4/35
=11/18+31/35+1/127+7/18+4/35
=(11/18+7/18)+(31/35+4/35)+1/127
=1+1+1/127
=2+1/127
=2\(\frac{1}{127}\)
=
Minh ngoc oi minh giu nguyen ket qua la hon so a
(10/99 + 11/199 - 12/299) . (1/2 - 1/3 + -1/6)
tinh chi tiet cang nhanh cang tot nhe!
(10/99 +11/199 -12/299).(1/2-1/3+-1/6)
=(10/99 +11/199 -12/299).0
=0
HOK TỐT
Đề bài: (10/99+11/199-12/299).(1/2-1/3+ -1/6)
=(10/99+11/199-12/299).(3/6-2/6+ -1/6)
=(10/99+11/199-12/299).(3-2+ -1/6)
=(10/99+11/199-12/299).0
=0.
Hok tốt nhé !
\(\left(\frac{10}{99}+\frac{11}{199}-\frac{12}{299}\right).\left(\frac{1}{2}-\frac{1}{3}+\frac{-1}{6}\right)\)
\(=\left(\frac{10}{99}+\frac{11}{199}-\frac{12}{299}\right).0\)
\(=0\)
~ Hok tốt ~
1/2 × x +150 ℅ × x = 2004
1/2 × x + 1/8x = 3/4
2- (3/4-x)= 7/12
(2x -4,5):3/4-1/3 =1
Bai 2 tinh gia tri bieu thuc
Q = (1/99+12/999+123/999)×(1/2-1/3-1/6)
℅ la phan tram
Nhanh nhe ai dung minh se thich va keu goi ban be thich nua thank you
2,
Q=\(\left(\frac{1}{99}+\frac{12}{999}+\frac{123}{999}\right)x\left(\frac{1}{2}-\frac{1}{3}-\frac{1}{6}\right)\)
= \(\left(\frac{1}{99}+\frac{12}{999}+\frac{123}{999}\right)x\left(\frac{3+\left(-2\right)+\left(-1\right)}{6}\right)\)
=\(\left(\frac{1}{99}+\frac{12}{999}+\frac{123}{999}\right)x0\)
Vậy Q=0
Giai giup minh bai toan tinh nhanh nay nhe
a) 7/4+7/28+7/70+7/130
b) 99/98-98/97+1/97×98
c) 51×115+37×102-17×45-37×2
d) 10+1/90-1/72-1/56-1/42-1/30-1/20-1/6-1/2
a)=7x(1/4+1/28+1/70+1/130)
=7x(1/1x4+1/4x7+1/7x10+1/10x13)
=7x(1-1/4+1/4-1/7+1/7-1/10+1/10-1/13)
=7x(1+1/13)
=7x14/13=98/13
Các câu còn lại p dựa theo cách trên làm nốt nhé!!!
1+2-3-4+...+97+98-99-100
nhanh len minh tick cho nhe
Dễ:
1 + 2 - 3 -4 + ... + 97 + 98 - 99 - 100
= ( 1+ 2 - 3 - 4) + ....+ ( 97 + 98 - 99 -100)
= -4 + -4 + ... + (-4) ( có tất cả 25 cặp nên có 25 số -4)
= -4 x 25
=-100
1+2-3-4+...+97+98-99-100
=(1+2-3-4)+...+(97+98-99-100)
=-4+...+(-4)=(-4)*25=-100
Tinh nhanh
[1-1/2] nhan [1-1/3] nhan [1-1/4] nhan [1-1/5] nhan ...nhan [1-1/100]
lam tung buoc cho minh nhe
\(\left(1-\frac{1}{2}\right)\times\left(1-\frac{1}{3}\right)\times\left(1-\frac{1}{4}\right)\times\left(1-\frac{1}{5}\right)...\times\left(1-\frac{1}{100}\right)\)
=\(\frac{1}{2}\times\frac{2}{3}\times\frac{3}{4}\times\frac{4}{5}\times...\times\frac{99}{100}\)
=\(\frac{1\times2\times3\times4\times...\times99}{2\times3\times4\times5\times...\times100}\)
= \(\frac{1}{100}\)
giai giup minh nhe
tinh nhanh:1*2*3*4/8 *9*10*7
mik nhân từng số mà sai thì đừng có k nha hihihi thật ra bằng kết quả này hihihi
1*2*3*4/8 *9*10*7=15.120
ko bít đâu nha hihi
gái xinh hok\(\frac{2x3x2x2}{2x2x2x3x3x2x5x7}\)=\(\frac{1}{2x3x5x7}\)=\(\frac{1}{210}\)
khanh ly oi tinh nhanh ma cach ban la tinh cham
de bai 1*2*3*4/8*9*10*7
cach minh la 8/4;10/2;9/3;7/1 nhung 1 dung truoc nen tanh 1/7 va=1/7
8/4=2;10/2=5;9/3=3 nen ket qua la phan so va =30/7