The quadratic equation 2x^2 + 8x + 1 = 0 has roots x1 and x2. Write down the value of x1+x2 and x1*x2 and find the value of x1^2 + x2^2
If a quadratic equation is of the form : ax^2 +bx +c =0and has roots x1 and x2, then the following statements are true:x1+x2 = - b/ax1x2 = c/aIn our case: x1+x2 = - 8/2 = -4and x1x2 = 1/2Now, x1^2 + x2^2 = (x1+x2)^2 -2x1x2= (-4)^2 -2 * 1/2 = 16 - 1 = 15
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