tìm x
a,x-1 trên 9 =8 phần3
b,-x trên 4 =-9 phần 4
c,x trên 4=18 trên x+1
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(\dfrac{37\cdot5^4}{25^2}=\dfrac{37\cdot5^4}{5^4}=37\\ \dfrac{2^4\cdot2^6\cdot3^8\cdot9^2}{4^4\cdot3^{11}}=\dfrac{2^{10}\cdot3^8\cdot3^4}{2^8\cdot3^{11}}=2^2\cdot3=12\\ \dfrac{3\cdot9^4\cdot9^3}{3^2\cdot9}=\dfrac{3\cdot3^8\cdot3^6}{3^2\cdot3^2}=3^{11}\\ \dfrac{125\cdot5\cdot64-25^3\cdot10\cdot4}{5^7\cdot8}=\dfrac{5^3\cdot5\cdot2^6-5^6\cdot2\cdot5\cdot2^2}{5^7\cdot2^3}=\dfrac{5^4\cdot2^3\left(2^3-5^3\right)}{5^7\cdot2^3}=\dfrac{8-125}{5^3}=\dfrac{-117}{125}\)
\(P=\frac{3}{x+3}+\frac{1}{x-3}-\frac{18}{9-x^2}\)
a) Điều kiện: \(x\ne3;x\ne-3\)
b) \(P=\frac{3}{x+3}+\frac{1}{x-3}-\frac{18}{9-x^2}\)
\(P=\frac{3.\left(x-3\right)}{\left(x+3\right).\left(x-3\right)}+\frac{x+3}{\left(x-3\right).\left(x+3\right)}-\frac{-18}{\left(x-3\right).\left(x+3\right)}\)
\(P=\frac{3x-9+x+3+18}{\left(x+3\right).\left(x-3\right)}=\frac{4x+12}{\left(x-3\right).\left(x+3\right)}=\frac{4.\left(x+3\right)}{\left(x-3\right).\left(x+3\right)}=\frac{4}{x-3}\)
c) \(\frac{4}{x-3}=4\Leftrightarrow4=\left(x-3\right).4\Leftrightarrow4x-12=4\Leftrightarrow4x=16\Leftrightarrow x=4\)
1b)\(\frac{7}{19}x\frac{8}{11}+\frac{3}{11}:\frac{19}{7}-\frac{2}{-19}=\frac{7}{19}x\frac{8}{11}+\frac{3}{11}x\frac{7}{19}+\frac{2}{19}=\left(\frac{8}{11}+\frac{3}{11}\right)\frac{7}{19}+\frac{2}{19}=\frac{7}{19}+\frac{2}{19}=\frac{9}{19}\)
c)\(4\left(\frac{4}{9}+\frac{7}{11}-\frac{4}{9}\right)=4\frac{7}{11}\)
từ rồi làm tiếp
1,
\(\frac{25}{12}+\left(\frac{-4}{12}\right)=\frac{7}{4}\)
\(\frac{-10}{8}+\frac{15}{4}=\frac{5}{2}\)
\(\frac{3}{8}+\frac{-14}{6}=\frac{-47}{24}\)
\(\frac{350}{150}+\left(\frac{-200}{360}\right)=\frac{16}{9}\)
\([\frac{5}{8}+\left(\frac{-3}{4}\right)]+\frac{15}{6}=\frac{-1}{8}+\frac{15}{6}=\frac{19}{8}\)
\(\frac{7}{3}+[\left(\frac{-5}{6}\right)+\left(\frac{-2}{3}\right)]=\frac{7}{3}+\left(\frac{-3}{2}\right)=\frac{5}{6}\)
a) Có \(\frac{x-1}{9}\)=\(\frac{8}{3}\)
=> \(\left(x-1\right)\times3=8\times9\)
=>\(\left(x-1\right)\times3=27\)
=>\(x-1=27:3\)=>x-1=9=>x=9+1=10
Vậy x=10
b) Có \(\frac{-x}{4}\)=\(\frac{9}{4}\)
Vì 2 phân số này bằng nhau mà có mẫu bằng nhau nên tử cũng phải bằng nhau hay x=-9
c) Có \(\frac{x}{4}=\frac{18}{x+1}\Rightarrow x\left(x+1\right)=18\cdot4=72\)\(\Rightarrow x\times x+x\times1=72\)\(\Rightarrow2x+x=72\Rightarrow3x=72\Rightarrow x=72:3=9\)
Vậy x=9