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Question
Find the roots of the quadratic equation by using the quadratic formula in the following:
2x2 – 3x – 5 = 0
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Solution
The quadratic formula for finding the roots of quadratic equation
ax2 + bx + c = 0, a ≠ 0 is given by,
x = `(-b +- sqrt(b^2 - 4ac))/(2a)`
∴ x = `(-(-3) +- sqrt(3^2 - 4(2)(-5)))/(2(2))`
= `(3 +- sqrt(49))/4`
= `(3 +- 7)/4`
= `5/2, -1`
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