For what value of K does the equation 2x^2-Kx+8=0 have equal roots?
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We must have b^2 - 4ac =0. So what is k?
Originally Posted by ceasar_19134 For what value of K does the equation 2x^2-Kx+8=0 have equal roots? The roots may be found from the quadratic formula:
x = (K +/- sqrt(K^2-64))/4
These roots are equal when the discriminant (the stuff under the square root)
is zero. So the value/s of K you seek is/are the solution/s of:
K^2-64 = 0