Consider the graph of the cosine function shown below.
this is not \(\cos(x)\) this is \(4\cos(2x)\)
oh sorry, what was the question?
Oops my bad. Find the period and amplitude of the cosine function.
if the question was "what function is this" then i gave away the answer
ok amplitude you see with your eyeballs cosine goes from 1 to minus 1, with amplitude 1 this one goes from 4 to minus 4, so amplitude is ___ ?
4
ok good, and that is why i knew it was \(y=4\cos(bx)\) period you also see with your eyeballs can you see it?
Then at what values of theta for \[0 \le \theta \le 2 \pi\] do the maximum value(s), minimum values(s), and zeros occur?
lets get the period first, your last question is trivial max is 4, min is -4 and you can see what value of \(x\) gets it do you see the period?
is the period 0?
?
wheres the period
period is a length, the length over the \(x\) axis for which the function repeats
oh so its 4
for sine and cosine the period is \(2\pi\) because \(\sin(x)=\sin(x+2\pi)\)
oh no lets go slow the amplitude is 4
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period is the length from \(a\) to \(b\)
its 2
your function pictured goes from 4 to -4 and back up to 4 all in an interval of length \(\pi\)
2 pi
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