Докажите тождество:
- \({\largeа)}\ (x+1)^2=x^2+2x+1;\)
- \(\phantom{\largeа)}\ (x+1)^2=(x+1)(x+1)=\ \)
- \({\largeб)}\ (x-1)^2=x^2-2x+1;\)
- \({\largeв)}\ (x-1)(x^2+x+1)=x^3-1;\)
- \(\phantom{\largeв)}\ (x-1)(x^2+x+1)=x^3-x^2+x^2-x+\ \)
- \({\largeг)}\ (x+1)(x^2-x+1)=x^3+1.\)