Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
A = ( - 5)^32 . 20^43 / ( -8 )^29 . 125^25
= 5^32 . 20^43 / ( -8 )^29 . 125^25
= 5^32 . 20^43 / ( -8 )^29 . ( 5^3 )^25
= 5^32 . 20^43 / ( -8 )^29 . 5^75
= 20^43 / ( -8 )^29 . 5^43
= ( 4 . 5 )^43 / ( -8 )^29 . 5^43
= 4^43 . 5^43 / ( -8 )^29 . 5^43
= 4^43 / ( -8 )^29
= ( 2^2 )^43 / ( -2^3 )^29
= 2^86 / -2^87
\(P=\left(x+5\right)\left(ax^2+bx+25\right)\) (Sửa =25 thành +25)
\(Q=x^3+125=x^3+5^3=\left(x+5\right)\left(x^2-5x+25\right)\) (Sửa =25 thành +25)
Để \(P=Q\Rightarrow\left(ax^2+bx+25\right)=\left(x^2-5x+25\right)\)
\(\Rightarrow\left\{{}\begin{matrix}a=1\\b=-5\end{matrix}\right.\)
Từ 1x4+2x5+...+277x280
=(1+2+...+277)x(4+5+..+280)(Tính tổng các dãy số,Ta được)
=38503x39334=1514477002
(x/2-3)5=32
<=>(x/2-3)5=25
<=>x/2-3=2
<=>x=(2+3).2
<=>x=10
!!!!!CHÚC!!MAY!!MẮN!!!!!
\(\left(-5\right)^{32}\cdot20^{13}=5^{13}\cdot20^{13}\cdot5^{19}=5^{19}\cdot10^{13}\)
\(\left(-8\right)^{29}\cdot125^{25}=\left(-8\right)^{25}\cdot125^{25}\cdot8^4=\left(-1000\right)^{25}\cdot8^4\)
a, (-0,2)2 \(\times\) 5 - \(\dfrac{2^{13}\times27^3}{4^6\times9^5}\)
= 0,04 \(\times\) 5 - \(\dfrac{2^{13}\times3^9}{2^{12}\times3^{10}}\)
= 0,2 - \(\dfrac{2}{3}\)
= \(\dfrac{2}{10}\) - \(\dfrac{2}{3}\)
= - \(\dfrac{7}{15}\)
b, \(\dfrac{5^6+2^2.25^3+2^3.125^2}{26.5^6}\)
= \(\dfrac{5^6+4.5^6+8.5^6}{26.5^6}\)
= \(\dfrac{5^6.\left(1+4+8\right)}{26.5^6}\)
= \(\dfrac{1}{2}\)
\(\frac{x+5}{20}+\frac{x+5}{21}+\frac{x+5}{32}=\frac{x+5}{23}+\frac{x+5}{54}\)
\(\Leftrightarrow\frac{x+5}{20}+\frac{x+5}{21}+\frac{x+5}{32}-\frac{x+5}{23}-\frac{x+5}{54}=0\)
\(\Leftrightarrow\left(x+5\right)\left(\frac{1}{20}+\frac{1}{21}+\frac{1}{32}-\frac{1}{23}-\frac{1}{54}\right)=0\)
\(\Leftrightarrow x+5=0\)
\(\Leftrightarrow x=-5\)
\(\left(\frac{2}{5}\right)^{\text{x}+1}\cdot4=\frac{32}{125}\)
\(\Rightarrow\left(\frac{2}{5}\right)^{\text{x}+1}=\frac{32}{125}\div4\)
\(\Rightarrow\left(\frac{2}{5}\right)^{\text{x}+1}=\frac{8}{125}\)
\(\Rightarrow\left(\frac{2}{5}\right)^{\text{x}+1}=\left(\frac{2}{5}\right)^3\)
\(\Rightarrow x+1=3\Rightarrow x=3-1=2\)
Vậy x = 2