\(F=2x^2+4x+3\)
\(=2\left(x^2+2x+1\right)+1\)
\(=2\left(x+1\right)^2+1\)\(>\)\(0\) (với mọi x)
\(G=3x^2-5x+3\)
\(=3\left(x^2-\frac{5}{3}x\right)+3\)
\(=3\left(x^2-2.\frac{5}{6}x+\frac{25}{36}\right)+\frac{11}{12}\)
\(=3\left(x-\frac{5}{6}\right)^2>0\) với mọi x
\(F=2x^2+4x+3\)
\(=2\left(x^2+2x+\frac{3}{2}\right)\)
\(=2\left(x+1\right)^2+1\ge1>0\)
vay F luon duong voi moi gt cua x
\(G=3x^2-5x+3=3\left(x^2-\frac{5}{3}x+1\right)=3\left(x^2-2x\frac{5}{6}+\frac{25}{36}+\frac{11}{36}\right)\)
\(=3\left(x-\frac{5}{6}\right)^2+\frac{11}{12}\ge\frac{11}{12}>0\)
vay......................................
neu co sai bn thong cam nha
