SOLUTION: If a and B are the root of the equation {{{2x^2-7x-3}}}=0 find the values of i. {{{3/a+3/B}}} ii.{{{aB^2 + a^2B}}}

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Question 1003150: If a and B are the root of the equation 2x%5E2-7x-3=0
find the values of
i. 3%2Fa%2B3%2FB
ii.aB%5E2+%2B+a%5E2B
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
2x^2 -7x -3 = 0
divide both sides of = by 2
x^2 -(7/2)x -(3/2) = 0
add (3/2) to both sides of =
x^2 -(7/2)x = 3/2
now complete the square to solve quadratic
x^2 -(7/2)x + 49/16 = 24/16 + 49/16
(x -(7/4))^2 = 73/16
x = (7/4) + (3/4)*sqrt(7)
let a = (7/4) + (3/4)*sqrt(7) = 3.734313483 approx 3.73
let B = (7/4) - (3/4)*sqrt(7) = −0.234313483 approx -0.23
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i) 3/3.73 + 3/-0.23 = −12.239188717 approx -12.24
ii) (3.73)*(-0.23)^2 + (3.73)^2*(-0.23) = −3.00265 approx -3