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Differentiation of exponential and logarithmic functions — Question 239

Original QCE Vault practice · 1 mark

Q239 · Practice questionTechnology-freeSimple familiar1 mark

QUESTION 239

A lantern display has brightness B(t)=120e−0.3tB(t)=120e^{-0.3t}, where tt is measured in minutes. Which expression gives B′(t)B^{\prime}(t)?
(A)
−120e−0.3t-120e^{-0.3t}
(B)
−36e−0.3t-36e^{-0.3t}
(C)
36e−0.3t36e^{-0.3t}
(D)
120e−0.3t−0.3120e^{-0.3t}-0.3
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