- Mình có thể giúp bài 1 :)

 5^x +  5^ ( x + 2 ) = 650

5^x +  5^x . 5² = 650

 5^x .( 1 + 25 ) = 650

 5^x . 26 = 650 

5^x = 650 : 26

 5^x = 25

 5^x = 5² 

=> x = 2 

Vậy x = 2 

The Reflection Of Light~ Ủa đề  là 5^x-5^x+2= 650 sao ông lại đổi thành 5^x-5^(x+2) zậy

a)5^(x-2)(x+3)=1

=>5^(x-2)(x+3)=5⁰

=>(x-2)(x+3)=0

=>x-2=0=>x=2.

Và x+3=0=>x=-3.

Vậy x=2 và x=-3.

b)Câu này mik ko làm dc.

c)x.(6-x)²⁰⁰³=(6-x)²⁰⁰³​

=>x=(6-x)²⁰⁰³​:(6-x)²⁰⁰³​

=>x=1.

Vậy x=1.

d)2.3^x=10.3¹²+8.3¹²

=>2.3^x=2.

Bài 1

a.\(\frac{-3}{4}\)-y:\(\frac{1}{5}\)=\(\frac{9}{28}\)

                y:\(\frac{1}{5}\)=\(\frac{-15}{14}\)

                          y= \(\frac{-3}{14}\)

b.5^x + 5^x+2=650

5^x . 1 + 5^x + 5²=650

5^x(1+25)=650

5^x.26=650

5^x=25

x=2

a)\(\dfrac{-6}{11}:\left(\dfrac{3}{5}.\dfrac{4}{11}\right)=\dfrac{-5}{2}\)

b)\(\dfrac{7}{12}+\dfrac{5}{12}:6-\dfrac{14}{30}=\dfrac{67}{370}\)

c)\(\left(\dfrac{4}{5}+\dfrac{1}{2}\right):\left(\dfrac{3}{13}-\dfrac{8}{13}\right)=-\dfrac{169}{50}\)

d)\(\left(\dfrac{2}{3}-\dfrac{1}{4}+\dfrac{5}{11}\right):\left(\dfrac{5}{12}+1-\dfrac{7}{11}\right)=\dfrac{115}{103}\)

Bài 1 :

\(a)x=\frac{7}{25}+\left(-\frac{1}{5}\right)\)

    \(x=\frac{2}{25}\)

\(b)x=\frac{5}{11}+\left(\frac{4}{-9}\right)\)

    \(x=\frac{1}{99}\)

Mấy câu kia dễ tự làm :>

A) 7/12+5/12 : 6 -11/36

=7/12 + 5/72 -11/36

=47/72-11/36

=25/72

Lời giải:

$D=(1+1+...+1)-(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+...+\frac{1}{650})$

$=25-(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+...+\frac{1}{25.26})$

$=25-(1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{25}-\frac{1}{26})$

$=25-(1-\frac{1}{26})=24+\frac{1}{26}$