c)5².7³.11².x+5².7².11=0

<=>5².7².11.(7.11.x+1)=0

<=>77x+1=0 do 5².7².11 khác 0

<=>77x=-1

<=>x=-1/77

b)5².7³.11².x-5².7².11⁴=0

<=>5².7².11².(7x-11²)=0

<=>7x-121=0 do 5².7².11² khác 0

<=>7x=121

<=>x=121:7

<=>x=121/7

1) \(2^{x+1}\cdot2^{2014}=2^{2015}\)\(\Leftrightarrow2^{2014x+2014}=2^{2015}\)\(\Leftrightarrow2014x+2014=2015\)\(\Leftrightarrow x=\frac{1}{2014}\)

2) \(7x-2x=\frac{6^{17}}{6^{15}}+\frac{44}{11}\)\(\Leftrightarrow5x=6^2+4=36+4=40\)\(\Leftrightarrow x=\frac{40}{5}=8\)

3) \(3^x=9\)\(\Leftrightarrow3^x=3^2\)\(\Leftrightarrow x=2\)

4) \(7x-x=\frac{5^{21}}{5^{19}}+3\cdot2^2-7^0\)\(\Leftrightarrow6x=5^2+3\cdot4-1=25+12-1=36\)\(\Leftrightarrow x=6\)

5) \(4^x=64\)\(\Leftrightarrow4^x=4^3\)\(\Leftrightarrow x=3\)

6) \(9^{x-1}=9\)\(\Leftrightarrow x-1=1\)\(\Leftrightarrow x=0\)

7) \(\frac{2^x}{2^5}=1\)\(\Leftrightarrow2^{x-5}=2^0\)\(\Leftrightarrow x-5=0\)\(\Leftrightarrow x=5\)

8) \(\left(5x-9\right)^3=216\)\(\Leftrightarrow\left(5x-9\right)^3=6^3\)\(\Leftrightarrow5x-9=6\)\(\Leftrightarrow5x=15\)\(\Leftrightarrow x=3\)

9) \(5\cdot3^{7x-11}=135\)\(\Leftrightarrow5.3^{7x-11}=5.3^3\)\(\Leftrightarrow3^{7x-11}=3^3\)\(\Leftrightarrow7x-11=3\)\(\Leftrightarrow7x=14\Leftrightarrow x=2\)

10) \(2.3^x=19\cdot3^8-81^2\)\(\Leftrightarrow2.3^x=19\cdot3^8-3^8=18.3^8=2.3^{11}\)\(\Leftrightarrow3^x=3^{11}\Leftrightarrow x=11\)

Đây là cách làm của mình. Bạn có thể chỉnh sửa tuỳ ý theo cách làm của bạn nhé ^^

Học tốt ^3^

tich minh cho minh len thu 8 tren bang sep hang cai

\(\frac{2^{10}\cdot3^{10}-2^{10}\cdot3^9}{2^9\cdot3^{10}}=\frac{2^{10}\cdot3^9\left(3-1\right)}{2^9\cdot3^{10}}=\frac{2^{11}\cdot3^9}{2^9\cdot3^{10}}=\frac{2^2}{3}=\frac{4}{3}\)

còn câu b cậu ạ

559Tiểu Yêu Pi Pi

1500-{125 x 8-11 x[343 :7 -5 x 8+8 x (121 - 121)]}

=1500-{125 x 8 - 11 x[343 : 7 - 5 x 8+8 x 0]}

=1500-{125 x 8 -11 x [ 49-40+0]}

=1500-{125 x 8-11  x 9}

=1500 -{1000-99}

=1500-901

=599 tick mình nha

Câu a:

(7\(^{2017}\) - 7\(^{2015}\)) ⋮ (7\(^{2014}\).7)

= 7\(^{2015}\).(7\(^2\) - 1) ⋮ 7\(^{2015}\)

= (7\(^{2015}\) : 7\(^{2015}\)).(49 - 1)

= 1.48

= 48

Câu b:

(2\(^{13}\) + 2\(^5\)) : (2\(^{10}\) + 2\(^2\))

= 2\(^5.\)(2\(^8\) + 1):[2\(^2\).(2\(^8\) + 1)]

= (2\(^5:2^2\)).[(\(2^8+1):\left(2^8+1\right)\)]

= 2\(^3\).1

= 8