If x^2−14x+1=0, what is the value of x+1/x?
\(\frac{x+1}{x}\)?
no \[x + \frac{ 1 }{ x }\]
@satellite73
you have to find (x^2 +1)/x from the given equation, you can easily see what x^2 +1 is rest is a piece of cake.
huh?
x^2 - 14x + 1 =0 so x^2 +1 = ?
14x?
right and you have to find the value of (x^2 + 1)/x
x = 14, 13 right?
14,13 ? what ?
oh...i remember now...the sum of the roots and its reciprocal of a quadratic equation is just -b
thus -b = 14
thats not true. Thats only true when a=c=1, which was your case here.
not 1, its true when a=c.
1) find the zeros, \(x_1\) and \(x_2\) 2) compute \(x_1+\frac{1}{x_1}\)
oh....what if \[a \neq c \]?
if a not equals c, then thats not true then you might need to find the roots separately , or see if anything alternative is applicable. In this case, you don;t need to find the respective roots.
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