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Show that the equation `x^(2)+6x+6=0` has real roots ad solve it. |
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Answer» The given equation is `x^(2)+6x+6=0.` Comparing it with `ax^(2)+bx+c=0,` we get `a-1,b=6" and "c=6.` `:." "D=(b^(2)-4ac)=(36-4xx1xx6)=12gt0.` So, the given equation has real roots. Now, `sqrt(D)=sqrt(12)=2sqrt(3).` `:." "alpha=(-b+sqrt(D))/(2a)=((-6+2sqrt(3)))/(2xx1)=((-6+2sqrt(3)))/(2)=(-3+sqrt(3)),` `beta=(-b-sqrt(D))/(2a)=((-6-2sqrt(3)))/(2xx1)=((-6-2sqrt(3)))/(2)=(-3-sqrt(3)).` Hence, `(-3+sqrt(3))` and `(-3-sqrt(3))` are the roots of the given equation. |
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