Bạn đang xem: Rèn luyện tư duy chiếm trọn điểm 8
$color#FF6800 2 color#FF6800 x ^ color#FF6800 2 color#FF6800 - color#FF6800 x color#FF6800 + color#FF6800 1 = color#FF6800 0 $
$color#FF6800 x ^ color#FF6800 2 color#FF6800 - color#FF6800 dfrac 1 2 color#FF6800 x color#FF6800 + color#FF6800 dfrac 1 2 = color#FF6800 0 $
$color#FF6800 x ^ color#FF6800 2 color#FF6800 - color#FF6800 dfrac 1 2 color#FF6800 x color#FF6800 + color#FF6800 dfrac 1 2 = color#FF6800 0 $
$ $ Hãy đổi khác biến đổi vế trái của phương trình bậc nhị thành dạng bình phương của một hiệu hoặc một tổng $ $
$left ( color#FF6800 x color#FF6800 - color#FF6800 dfrac 1 4 ight ) ^ color#FF6800 2 color#FF6800 + color#FF6800 dfrac 1 2 color#FF6800 - left ( color#FF6800 dfrac 1 4 ight ) ^ color#FF6800 2 = color#FF6800 0 $
$left ( x - dfrac 1 4 ight ) ^ 2 color#FF6800 + color#FF6800 dfrac 1 2 color#FF6800 - left ( color#FF6800 dfrac 1 4 ight ) ^ color#FF6800 2 = 0$
$left ( x - dfrac 1 4 ight ) ^ 2 = color#FF6800 - color#FF6800 dfrac 1 2 color#FF6800 + left ( color#FF6800 dfrac 1 4 ight ) ^ color#FF6800 2 $
$left ( x - dfrac 1 4 ight ) ^ 2 = - dfrac 1 2 + left ( color#FF6800 dfrac 1 4 ight ) ^ color#FF6800 2 $
$left ( x - dfrac 1 4 ight ) ^ 2 = - dfrac 1 2 + dfrac color#FF6800 1 ^ color#FF6800 2 color#FF6800 4 ^ color#FF6800 2 $
$left ( color#FF6800 x color#FF6800 - color#FF6800 dfrac 1 4 ight ) ^ color#FF6800 2 = color#FF6800 - color#FF6800 dfrac 1 2 color#FF6800 + color#FF6800 dfrac 1 ^ 2 4 ^ 2 $
$left ( color#FF6800 x color#FF6800 - color#FF6800 dfrac 1 4 ight ) ^ color#FF6800 2 = color#FF6800 - color#FF6800 dfrac 7 16 $
$left ( color#FF6800 x color#FF6800 - color#FF6800 dfrac 1 4 ight ) ^ color#FF6800 2 = color#FF6800 - color#FF6800 dfrac 7 16 $
$color#FF6800 x color#FF6800 - color#FF6800 dfrac 1 4 = pm sqrt color#FF6800 - color#FF6800 dfrac 7 16 $
$color#FF6800 x color#FF6800 - color#FF6800 dfrac 1 4 = pm sqrt color#FF6800 - color#FF6800 dfrac 7 16 $
$color#FF6800 x = pm color#FF6800 dfrac sqrt 7 i 4 color#FF6800 + color#FF6800 dfrac 1 4 $
$color#FF6800 x = pm color#FF6800 dfrac sqrt 7 i 4 color#FF6800 + color#FF6800 dfrac 1 4 $
$eginarray l color#FF6800 x = color#FF6800 dfrac 1 4 color#FF6800 + color#FF6800 dfrac sqrt 7 i 4 \ color#FF6800 x = color#FF6800 dfrac 1 4 color#FF6800 - color#FF6800 dfrac sqrt 7 i 4 endarray$
$eginarray l color#FF6800 x = color#FF6800 dfrac 1 4 color#FF6800 + color#FF6800 dfrac sqrt 7 i 4 \ color#FF6800 x = color#FF6800 dfrac 1 4 color#FF6800 - color#FF6800 dfrac sqrt 7 i 4 endarray$
$eginarray l color#FF6800 x = color#FF6800 dfrac 1 + sqrt 7 i 4 \ color#FF6800 x = color#FF6800 dfrac 1 - sqrt 7 i 4 endarray$
$eginarray l x = dfrac 1 + sqrt 7 i 4 \ x = dfrac 1 - sqrt 7 i 4 endarray$
$color#FF6800 2 color#FF6800 x ^ color#FF6800 2 color#FF6800 - color#FF6800 x color#FF6800 + color#FF6800 1 = color#FF6800 0 $
$ $ Hãy sử dụng công thức nghiệm $ dfrac-bpmsqrtb^2-4ac2a $ nhằm giải phương trình bậc hai $ ax^2+bx+c=0$
$color#FF6800 x = color#FF6800 dfrac - left ( - 1 ight ) pm sqrt left ( - 1 ight ) ^ 2 - 4 imes 2 imes 1 2 imes 2 $
$x = dfrac color#FF6800 - left ( color#FF6800 - 1 ight ) pm sqrt left ( - 1 ight ) ^ 2 - 4 imes 2 imes 1 2 imes 2 $
$x = dfrac 1 pm sqrt left ( color#FF6800 - color#FF6800 1 ight ) ^ color#FF6800 2 - 4 imes 2 imes 1 2 imes 2 $
$color#FF6800 x = color#FF6800 dfrac 1 pm sqrt 1 ^ 2 - 4 imes 2 imes 1 2 imes 2 $
$eginarray l color#FF6800 x = color#FF6800 dfrac 1 + sqrt 7 i 4 \ color#FF6800 x = color#FF6800 dfrac 1 - sqrt 7 i 4 endarray$
$x = dfrac color#FF6800 - left ( color#FF6800 - 1 ight ) pm sqrt left ( - 1 ight ) ^ 2 - 4 imes 2 imes 1 2 imes 2 $
$x = dfrac 1 pm sqrt left ( color#FF6800 - color#FF6800 1 ight ) ^ color#FF6800 2 - 4 imes 2 imes 1 2 imes 2 $
$x = dfrac 1 pm sqrt color#FF6800 1 ^ color#FF6800 2 - 4 imes 2 imes 1 2 imes 2 $
$x = dfrac 1 pm sqrt 1 - 4 imes 2 color#FF6800 imes color#FF6800 1 2 imes 2 $
$x = dfrac 1 pm sqrt 1 color#FF6800 - color#FF6800 4 color#FF6800 imes color#FF6800 2 2 imes 2 $
$x = dfrac 1 pm sqrt color#FF6800 1 color#FF6800 - color#FF6800 8 2 imes 2 $
$x = dfrac 1 pm sqrt - 7 color#FF6800 2 color#FF6800 imes color#FF6800 2 $
$color#FF6800 2 color#FF6800 x ^ color#FF6800 2 color#FF6800 - color#FF6800 x color#FF6800 + color#FF6800 1 = color#FF6800 0 $
$color#FF6800 D = left ( color#FF6800 - color#FF6800 1 ight ) ^ color#FF6800 2 color#FF6800 - color#FF6800 4 color#FF6800 imes color#FF6800 2 color#FF6800 imes color#FF6800 1 $
$D = left ( color#FF6800 - color#FF6800 1 ight ) ^ color#FF6800 2 - 4 imes 2 imes 1$
Xem thêm: Ninh Bình: Giáo Viên Mầm Non Bỏ Việc, Trường Học Lo Lắng, Phòng Gd&Đt Gia Viễn
