Mathematics
Show that the equation 3x2 + 7x + 8 = 0 is not true for any real value of x.
Quadratic Equations
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Answer
Comparing 3x2 + 7x + 8 = 0 with ax2 + bx + c = 0 we get,
a = 3, b = 7 and c = 8.
We know that,
Discriminant (D) = b2 - 4ac = (7)2 - 4.(3).(8) = 49 - 96 = - 47; which is negative.
The equation has imaginary and unequal roots for all real values of x.
Hence, the equation 3x2 + 7x + 8 = 0 is not true for any real value of x.
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