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Question

Bài 1:1)$\left(\dfrac{-3}{2}\right)^x$=$\dfrac{9}{4}$

2)$3^{2x+2}=9^{10}$

3)$3^{3-2x}=27^{13}$

4)$5.3^x=7.3^5-2.3^5$

Giúp mk với

Lê Thị Ngọc Duyên · Accepted Answer

1. $\left(-\dfrac{3}{2}\right)^2=\dfrac{9}{4}$

$\Rightarrow\left(-\dfrac{3}{2}\right)^x=\left(-\dfrac{3}{2}\right)^2$

$\Rightarrow x=2$

2.$3^{2x+2}=9^{10}$

$\Rightarrow3^{2x+2}=\left(3^2\right)^{10}$

$\Rightarrow3^{2x+2}=3^{20}$

$\Rightarrow2x+2=20$

$\Rightarrow2x=18$

$\Rightarrow x=9$Câu trả lời: 1. $\left(-\dfrac{3}{2}\right)^2=\dfrac{9}{4}$

$\Rightarrow\left(-\dfrac{3}{2}\right)^x=\left(-\dfrac{3}{2}\right)^2$

$\Rightarrow x=2$

2.$3^{2x+2}=9^{10}$

$\Rightarrow3^{2x+2}=\left(3^2\right)^{10}$

$\Rightarrow3^{2x+2}=3^{20}$

$\Rightarrow2x+2=20$

$\Rightarrow2x=18$

$\Rightarrow x=9$

Lê Thị Ngọc Duyên · Answer

3)$3^{3-2x}=27^{13}$

$\Rightarrow3^{3-2x}=\left(3^3\right)^{13}$

$\Rightarrow3^{3-2x}=3^{39}$

$\Rightarrow3-2x=39$

$\Rightarrow2x=-36$

$\Rightarrow x=-18$

4)$5.3^x=7.3^5-2.3^5$

$\Rightarrow5.3^x=3^5\left(7-2\right)$

$\Rightarrow5.3^x=3^5.5$

$\Rightarrow3^x=3^5$

$\Rightarrow x=5$Câu trả lời: 3)$3^{3-2x}=27^{13}$

$\Rightarrow3^{3-2x}=\left(3^3\right)^{13}$

$\Rightarrow3^{3-2x}=3^{39}$

$\Rightarrow3-2x=39$

$\Rightarrow2x=-36$

$\Rightarrow x=-18$

4)$5.3^x=7.3^5-2.3^5$

$\Rightarrow5.3^x=3^5\left(7-2\right)$

$\Rightarrow5.3^x=3^5.5$

$\Rightarrow3^x=3^5$

$\Rightarrow x=5$

Bài 5: Lũy thừa của một số hữu tỉ