Giai 21
15/21 - 15/21. Nho giai day du nha. Ko thi dung mo ma tich
\(\frac{15}{21}-\frac{15}{21}=\frac{15-15}{21}=0\)
=\(\frac{15}{21}-\frac{15}{21}=\frac{15-15}{21}=\frac{0}{21}=0..\)
ok xong
\(\frac{15}{21}\)-\(\frac{15}{21}\)=\(\frac{15-15}{21}\)=\(\frac{0}{21}\)=
(49+4)-(37+7)+(32+21)-(21+23)=?
Ai giúp minh giai bài toán nay nhanh nhat thj minh tick cho!
[49+4]-[37+7]+[32+21]-[21+23]
=53-44+53-44
=9+53-44
=62-44
=18
giai bai nay cho minh voi
-20<x<21
Bạn ghi thiếu đề rồi
=> x = -19; -18; -17; -16; -15; -14;...; 0; 1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12; 13; 14; 15; 16; 17; 18; 19; 20
a,7/3.-5/2.15/21..4/-5
cac ban giai chi tiet cho minh nha
\(\dfrac{7}{3}.\dfrac{-5}{2}.\dfrac{15}{21}.\dfrac{-4}{5}=-\dfrac{46}{630}=-\dfrac{23}{315}\)
\(\dfrac{7}{3}x\dfrac{-5}{2}x\dfrac{15}{21}x\dfrac{4}{-5}\)
\(=\dfrac{7}{3}x\dfrac{-5}{2}x\dfrac{5}{7}x\dfrac{4}{-5}\)
\(=\dfrac{7x\left(-5\right)x5x4}{3x2x7x\left(-5\right)}\)
=\(=\dfrac{10}{3}\)
B= 2+2^3+2^5+2^7+2^9+2^11+...+2^2015+2^2017 cho 21
ai giai duoc cho 3 like\
giai thich ro nhe
5x-32=21+x-5
Giai dum voi moi nguoi
15(x+9)(x-3)(x+21)
giai ho mik nhe
Giai pt:
x-241/17+x-220/19+x-195/21+x-161/23=10
\(\dfrac{x-241}{17}+\dfrac{x-220}{19}+\dfrac{x-195}{21}+\dfrac{x-161}{23}=10\)
<=>\(\dfrac{x-241}{17}-1+\dfrac{x-220}{19}-2+\dfrac{x-195}{21}-3\dfrac{x-161}{23}-4=0\)
<=>\(\dfrac{x-258}{17}+\dfrac{x-258}{19}+\dfrac{x-158}{21}+\dfrac{x-158}{23}=0\)
<=>\(\left(x-258\right)\left(\dfrac{1}{17}+\dfrac{1}{19}+\dfrac{1}{21}+\dfrac{1}{23}\right)=0\)
vì 1/17+1/19+1/21+1/23 khcas 0
=>x-258=0<=>x=258
vậy...............
chcus bạn học tốt ^^
9+13+17+21+...+x=y va co tong so hang la 88 so hang.Giup giai bai nay voi!!!!!