Question

\(a,\sqrt{4x^2-4x+1}-5=0\)\(b,\left(2x-1\right)\left(2x+1\right)-35=0\)

Answer 1

Chứng minh hằng đẳng thức sau: \(\dfrac{\left(\sqrt{5}+2\right)^28\sqrt{5}}{\sqrt{5}-2}-\sqrt{5}+3=1\)

Answer 2

`a)\sqrt{4x^2-4x+1}-5=0`

`<=>\sqrt{(2x-1)^2}=5`

`<=>|2x-1|=5`

`<=>[(2x-1=5),(2x-1=-5):}<=>[(x=3),(x=-2):}`

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`b)(2x-1)(2x+1)-35=0`

`<=>4x^2-1-35=0`

`<=>x^2=9`

`<=>x=+-3`