help me!!!!
1) \(\left(x+1\right)^2-\left(x-1\right)\left(x+1\right)=3\)
\(\Leftrightarrow x^2+2x+1-\left(x^2-1\right)=3\)
\(\Leftrightarrow x^2+2x+1-x^2+1=3\)
\(\Leftrightarrow2x+2=3\)
\(\Leftrightarrow2x=1\)
\(\Leftrightarrow x=\dfrac{1}{2}\)
2) \(\left(3x-1\right)^2-x\left(9x+1\right)=15\)
\(\Leftrightarrow9x^2-6x+1-9x^2-x=15\)
\(\Leftrightarrow-7x+1=15\)
\(\Leftrightarrow-7x=15-1\)
\(\Leftrightarrow-7x=14\)
\(\Leftrightarrow x=-\dfrac{14}{7}\)
\(\Leftrightarrow x=-2\)
3) \(\left(4x+1\right)^2-2\left(8x^2-1\right)=24\)
\(\Leftrightarrow16x^2+8x+1-16x^2+2=24\)
\(\Leftrightarrow8x+3=24\)
\(\Leftrightarrow8x=21\)
\(\Leftrightarrow x=\dfrac{21}{8}\)
4) \(\left(x+2\right)^3-\left(x+1\right)^3-3x^2=7\)
\(\Leftrightarrow x^3+6x^2+12x+8-x^3-3x^2-3x-1-3x^2=7\)
\(\Leftrightarrow9x+7=7\)
\(\Leftrightarrow9x=7-7\)
\(\Leftrightarrow9x=0\)
\(\Leftrightarrow x=0\)
5) \(\left(x-1\right)\left(x^2+x+1\right)-\left(x-2\right)\left(x^2+2x+4\right)=2x\)
\(\Leftrightarrow\left(x^3-1\right)-\left(x^3-8\right)=2x\)
\(\Leftrightarrow x^3-1-x^3+8=2x\)
\(\Leftrightarrow7=2x\)
\(\Leftrightarrow x=\dfrac{7}{2}\)
6) \(\left(x+4\right)\left(x^2-4x+1\right)-\left(x+2\right)\left(x^2-2x+4\right)=3x-1\)
\(\Leftrightarrow\left(x^3+64\right)-\left(x^3+8\right)=3x-1\)
\(\Leftrightarrow x^3+64-x^3-8=3x-1\)
\(\Leftrightarrow56=3x-1\)
\(\Leftrightarrow3x=57\)
\(\Leftrightarrow x=\dfrac{57}{3}\)
\(\Leftrightarrow x=19\)
help me
help me =((