Gangadhar111990
In an experiment, the rate at which a certain bacterium grows is G. If G is a function of time t, such that
G= \( xt^3 \) +\( yt^2 \) + z , where x, y, and z are constants and t > 0. Is there a value of t for which G is negative?
(1) x > y > z
(2) z > 0
G(t) = \( xt^3 \) +\( yt^2 \) + z
Statement 1(1) x > y > zInference: x lies to the right of y which lies to the right of z on a number line.
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We do not know the position of zero.
Case 1: zero lies to the left of \(z\)
In this case, G(t) is always positive.
Is there a value of t for which G is negative? ⇒ No
Case 2: zero lies to the right of \(x\)
In this case, G(t) is always negative.
Is there a value of \(t\) for which G is negative? ⇒ Yes
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As we are getting two answers, the statement alone is not sufficient to answer the question.
Statement 2(2) z > 0
In this case, zero lies to the left of z. Hence, x, y, and z are always positive.
Therefore the value of G(t) is always positive.
Is there a value of t for which G is negative? ⇒ No
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Option B