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3 years ago

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The number of trees in a rainforest decreases each month by 0.5%. The forest currently has 2.5 billion trees. Which expression r

epresents how many trees will be left in 10 years. Group of answer choices

1 answer:

Blababa [14]3 years ago

8 0

Answer:

$y=2.5*10^9(0.005^{12 0}) \\\\$

Step-by-step explanation:

The above question is in the form of an exponential decay. The equation for an exponential decay is given by:

$y=ab^x$

where y and x are variables, b < 1, a is the initial value of y (that is the value of y when x = 0).

Let y represent the number of trees left and x represent the number of months. Given that there is currently 2.5 billion trees, therefore a = 2.5 * 10⁹, b = 0.5% = 0.005. The equations becomes:

$y=2.5*10^9(0.005^x)\\\\After\ ten\ years(x=10*12\ months=120\ months):\\\\y=2.5*10^9(0.005^{12 0}) \\\\$

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$\implies f(x,y,z)=e^{2xyz}+g(x,z)$

Differentiate both sides with respect to $x$ and

$\dfrac{\partial f}{\partial x}=\dfrac{\partial(e^{2xyz})}{\partial x}+\dfrac{\partial g}{\partial x}$

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$\implies h(z)=C$

for some constant $C$ . So

$f(x,y,z)=e^{2xyz}+4\sin(xz^2)+C$

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