If x + y = 7 and xy = 10, find x2 + y2.
29
Use the identity \(x^2 + y^2 = (x+y)^2 - 2xy\).
Substituting the given values, \(x^2 + y^2 = 7^2 - 2(10) = 49 - 20\).
This gives \(x^2 + y^2 = 29\).
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If k = c, then the roots of the equation are:
If \(\rm {k}=\frac{{c}}{2},({c} \neq 0)\), then the roots of the equation are :
What is the number of real roots of the equation?
What is the sum of all the roots of the equation?
If α and β are the distinct roots of equation x2 - x + 1 = 0, then what is the value of \(\left|\frac{\alpha^{100}+\beta^{100}}{\alpha^{100}-\beta^{100}}\right|\) ?
