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Question
In the following, determine whether the given quadratic equation have real roots and if so, find the roots:
3x2 - 5x + 2 = 0
Solution
We have been given, 3x2 - 5x + 2 = 0
Now we also know that for an equation ax2 + bx + c = 0, the discriminant is given by the following equation:
D = b2 - 4ac
Now, according to the equation given to us, we have,a = 3, b = -5 and c = 2.
Therefore, the discriminant is given as,
D = (-5)2 - 4(3)(2)
= 25 - 24
= 1
Since, in order for a quadratic equation to have real roots, D ≥ 0.Here we find that the equation satisfies this condition, hence it has real roots.
Now, the roots of an equation is given by the following equation,
`x=(-b+-sqrtD)/(2a)`
Therefore, the roots of the equation are given as follows,
`x=(-(-5)+-sqrt1)/(2(3))`
`=(5+-1)/6`
Now we solve both cases for the two values of x. So, we have,
`x=(5+1)/6`
`=6/6`
= 1
Also,
`x=(5-1)/6`
`=4/6`
`=2/3`
Therefore, the roots of the equation are `2/3` and 1.
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