(6x−2)2+(5x−2)2−4(3x−1)(5x−2)=0(6x−2)2+(5x−2)2−4(3x−1)(5x−2)=0
⇔36x2−24x+4+25x2−20x+4−12x(5x−2)+4(5x−2)=0⇔36x2−24x+4+25x2−20x+4−12x(5x−2)+4(5x−2)=0
⇔61x2−44x+8−60x2+24x+20x−8=0⇔61x2−44x+8−60x2+24x+20x−8=0
⇔x2=0⇔x2=0
⇔x=0⇔x=0
3(x−1)2−3x(x−5)=13(x−1)2−3x(x−5)=1
⇔3(x2−2x+1)−3x2+15x=1⇔3(x2−2x+1)−3x2+15x=1
⇔3x2−6x+3−3x2+15x=1⇔3x2−6x+3−3x2+15x=1
⇔9x=1−3⇔9x=1−3
⇔9x=−2⇔9x=−2
⇔x=−29⇔x=−29
(x−2)3−x2(x−6)=4(x−2)3−x2(x−6)=4
⇔x3−6x2+12x−8−x3+6x2=4⇔x3−6x2+12x−8−x3+6x2=4
⇔12x=12⇔12x=12
⇔x=1⇔x=1
(x−1)(x2+x+1)−x(x+2)(x−2)=5(x−1)(x2+x+1)−x(x+2)(x−2)=5
⇔x3−1−x(x2−4)=5⇔x3−1−x(x2−4)=5
⇔x3−1−x3+4x=5⇔x3−1−x3+4x=5
⇔4x=6⇔4x=6
⇔x=32⇔x=32
(x−1)3−(x+3)(x2−3x+9)+3(x2−4)=0(x−1)3−(x+3)(x2−3x+9)+3(x2−4)=0
⇔x3−3x2+3x−1−x3−27+3x2−12=0⇔x3−3x2+3x−1−x3−27+3x2−12=0
⇔3x−40=0⇔3x−40=0
⇔3x=40⇔3x=40
⇔x=403
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