a) ƯCLN(1,16) = 1.

b) 8 = 2³; 20 = 2².5

=> ƯCLN(8, 20) = 2² = 4.

c) 84 = 2². 3.7;  156 = 2².3.13

=> ƯCLN(84, 156) = 2².3 = 12.

d) 16 = 2⁴; 40 = 2³.5;  176 = 2⁴.11

=> ƯCLN(16, 40, 176) = 2³ = 8.

Đáp án C

\(\left(1,16-x\right).\frac{\frac{21}{4}}{7}=0,75\)

\(\left(1,16-x\right).0,75=0,75\)

\(1,16-x=0,75:0,75\)

\(1,16-x=1\)

\(x=1,16-1\)

\(x=0,16\)

\(a,\Rightarrow\left|x\right|=4+1,16=5,16\Rightarrow\left[{}\begin{matrix}x=5,16\\x=-5,16\end{matrix}\right.\\ b,\Rightarrow\left(3x-2\right)^3=\left(-\dfrac{5}{2}\right)^3\\ \Rightarrow3x-2=-\dfrac{5}{2}\\ \Rightarrow3x=-\dfrac{5}{2}+2=-\dfrac{1}{2}\\ \Rightarrow x=-\dfrac{1}{2}:3=-\dfrac{1}{6}\)

a)lxl - 1,16=4

lxl=4+1,16

lxl=5,16

=>x thuộc ( 5,16 ; -5,16)

a) \(\Rightarrow\left|x\right|=5,16\\ \Rightarrow\left[{}\begin{matrix}x=-5,16\\x=5,16\end{matrix}\right.\)

b) \(\Rightarrow\left(3x-2\right)^3=\left(\dfrac{-5}{2}\right)^3\\ \Rightarrow3x-2=-\dfrac{5}{2}\\ \Rightarrow3x=-\dfrac{1}{2}\\ \Rightarrow x=-\dfrac{1}{6}\)

hình như đề sai với lại lớp 4 chưa học số thập phân

x=0,16