Question

làm phần b,c,d thôi ạ

Answer 1

\(b,\left(x+5\right)^2=100\)

TH1:\(\left(x+5\right)^2=10^2\)

        \(\Rightarrow x+5=10\\ \Rightarrow x=10-5\\ \Rightarrow x=5\)

TH2:\(\left(x+5\right)^2=\left(-10\right)^2\)

         \(\Rightarrow x+5=-10\\ \Rightarrow x=-10-5\\ \Rightarrow x=-15\)

\(c,\left(2x-4\right)^2=0\\ \Rightarrow2x-4=0\\ \Rightarrow2x=0+4\\ \Rightarrow x=2:2\\ \Rightarrow x=1\)

\(d,\left(x-1\right)^3=-27\\ \Rightarrow\left(x-1\right)^3=\left(-3\right)^3\\ \Rightarrow x-1=-3\\ \Rightarrow x=-3+1\\ \Rightarrow x=-2\)

 

Answer 2

b) (x+5)²=100
    (x+5)²=10²
     x+5=10
     x=10-5
     x=5
c) (2x-4)²=0
    2x-4=0
    2x=4
      x=4:2
      x=\(\pm\)2
d)(x-1)³=-27
   (x-1)³=-3³
    x-1=-3
    x=-3+1
    x=-2