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प्रश्न
Solve the following quadratic equation.
5m2 + 2m + 1 = 0
उत्तर
5m2 + 2m + 1 = 0
a = 5, b = 2, c = 1
= b2 - 4ac
= 4 - 4 × 5 × 1
= 4 - 20
= -16
∴ The roots of the quadratic equation are not real.
m = `(-"b" ± sqrt("b"^2 - 4"ac"))/"2a"`
= `(-2 ± sqrt((2)^2 - 4 xx 5 xx 1))/(2 xx 5)`
= `(-2 ± sqrt(4 - 20))/10`
= `(-2 ± sqrt(-16))/10`
= `(-2 + 4 sqrt-1)/10`
= `(2(-1 + 2 sqrt-1))/10`
= `(-1 -2 sqrt1)/5`
So, the roots are not real as the discriminant is negative.
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