Question

Which two values of X are roots of the polynomial below 4x^2-6x+1

Answer 1

$4x^2-6x+1=0\\\\a=4,\ b=-6,\ c=1\\\\\Delta=b^2-4ac\\\\\Delta=(-6)^2-4(4)(1)=36-16=20\\\\\sqrt\Delta=\sqrt{20}=\sqrt{4\cdot5}=\sqrt4\cdot\sqrt5=2\sqrt5\\\\x_1=\dfrac{-b-\sqrt\Delta}{2a},\ x_2=\dfrac{-b+\sqrt\Delta}{2a}\\\\x_1=\dfrac{-(-6)-2\sqrt5}{2\cdot4}=\dfrac{3-\sqrt5}{4}\\\\x_2=\dfrac{-(-6)+2\sqrt5}{2\cdot4}=\dfrac{3+\sqrt5}{4}$