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Can y’all help me answer these questions

Can y’all help me answer these questions-example-1

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2.
f(x)=\frac18\left(\frac14\right)^(x-2)

Domain:
(-\infty,\infty), because any value of
x is allowed and gives a number
f(x).

Range:
(0,\infty), because
a^x>0 for any positive real
a\\eq0.

y-intercept: This is a point of the form
(0, f(0)). So plug in
x=0; we get
f(0)=\frac18\left(\frac14\right)^(-2)=\frac{4^2}8=2. So the intercept is (0, 2), or just 2. (Interestingly, you didn't get marked wrong for that...)

Asymptote: This can be deduced from the range; the asymptote is the line
y=0.

Increasing interval: Going from left to right, there is no interval on which
f(x) is increasing, since 1/4 is between 0 and 1.

Decreasing interval: Same as the domain;
f(x) is decreasing over the entire real line.

End behavior: The range tells you
f(x)>0, and you know
f(x) is decreasing over its entire domain. This means that
f(x)\to+\infty as
x\to-\infty, and
f(x)\to0 and
x\to+\infty.

3.
f(x)=\left(\frac32\right)^(-x)-7

Domain: Same as (2),
(-\infty, \infty).

Range: We can rewrite
f(x)=\left(\frac23\right)^x-7.
\left(\frac23\right)^x>0 for all
x, so
\left(\frac23\right)^x-7>-7 for all
x. Then the range is
(-7,\infty).

y-intercept: We have
f(0)=\left(\frac32\right)^0-7=1-7=-6, so the intercept is (0, -6) (or just -6).

Asymptote:
y=-7

Increasing interval: Not increasing anywhere

Decreasing interval:
(-\infty,\infty)

End behavior: Similar to (2), but this time
f(x)\to+\infty as
x\to-\infty and
f(x)\to-7 as
x\to+\infty.

User Stanowczo
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