(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

1) When a camera flash goes off, the batteries immediately begin to recharge the flash's capacitor, which stores electric charge given by the following. (The maximum charge capacity is M and t is measured in seconds.)

Q(t) = M(1 - e-t/a)

(a) Find the inverse of this function and explain its meaning.

2. Let f(x) = 2 + x2 + tan(πx/2), where -1 < x < 1.

(a) Find f(f -1(4)).

2. Relevant equations

n/a

3. The attempt at a solution

(1) Q = M(1 - e^-t/a)

Q/M = 1 - e^-t/a

e^-t/a = 1 - Q/M

-t/a (ln e) = ln(1 - Q/M)

-t/a = ln(1 - Q/M)

t = -a[ln(1 - Q/M)]

That's not right.

(#2.) x = 2 + y^2 + tan(π*y/2)

4 = 2 + y^2 + tan(π*y/2)

*plug into wolfram alpha... y~0.642

f(x) = 2 + x2 + tan(πx/2) original formula

f(.642)= 2 + (.642^2) + tan (.642π/2)

f(.642)=2.4293

That's not right either.

I'm not really seeing where I went wrong in either of them..any help is appreciated.

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# Homework Help: Inverse problemshelp please!

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