Find all real zeros of f:
f(x)= ln(3x^2 + 27)
f(x)= ln(3x^2 + 27)
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this has no real roots but 2 complex roots
ln(3x^2+27 = 0
3x^2+27 = e^0 = 1
x^2 = -26/3
x = ±i*sqrt(26/3)
ln(3x^2+27 = 0
3x^2+27 = e^0 = 1
x^2 = -26/3
x = ±i*sqrt(26/3)
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This logarithmic can never be zero with real roots, it only has imaginary roots.
ln1 = 0
So when does 3x^2 + 27 = 1?
Let's see:
3x^2 = -26
x^2 = -26/3
x = sqrt(-26/3)
This has no real solutions since you cannot have a negative square root.
ln1 = 0
So when does 3x^2 + 27 = 1?
Let's see:
3x^2 = -26
x^2 = -26/3
x = sqrt(-26/3)
This has no real solutions since you cannot have a negative square root.