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We're asked to simplify 8 plus
5 times 4 minus, and then in
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parentheses, 6 plus 10
divided by 2 plus 44.
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Whenever you see some type of
crazy expression like this
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where you have parentheses and
addition and subtraction and
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division, you always want
to keep the order of
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operations in mind.
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Let me write them
down over here.
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So when you're doing order of
operations, or really when
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you're evaluating any
expression, you should have
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this in the front of your brain
that the top priority
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goes to parentheses.
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And those are these little
brackets over here, or however
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you want to call them.
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Those are the parentheses
right there.
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That gets top priority.
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Then after that, you want to
worry about exponents.
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There are no exponents in this
expression, but I'll just
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write it down just for future
reference: exponents.
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One way I like to think about it
is parentheses always takes
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top priority, but then after
that, we go in descending
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order, or I guess we should
say in-- well, yeah, in
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descending order of how fast
that computation is.
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When I say fast, how
fast it grows.
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When I take something to an
exponent, when I'm taking
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something to a power, it grows
really fast. Then it grows a
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little bit slower or shrinks
a little bit slower if I
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multiply or divide,
so that comes
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next: multiply or divide.
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Multiplication and division
comes next, and then last of
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all comes addition
and subtraction.
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So these are kind of the
slowest operations.
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This is a little bit faster.
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This is the fastest operation.
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And then the parentheses,
just no matter
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what, always take priority.
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So let's apply it over here.
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Let me rewrite this
whole expression.
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So it's 8 plus 5 times 4 minus,
in parentheses, 6 plus
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10 divided by 2 plus 44.
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So we're going to want to do the
parentheses first. We have
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parentheses there and there.
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Now this parentheses is pretty
straightforward.
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Well, inside the parentheses
is already evaluated, so we
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could really just view
this as 5 times 4.
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So let's just evaluate that
right from the get go.
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So this is going to result in
8 plus-- and really, when
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you're evaluating the
parentheses, if your evaluate
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this parentheses, you literally
just get 5, and you
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evaluate that parentheses, you
literally just get 4, and then
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they're next to each other,
so you multiply them.
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So 5 times 4 is 20 minus--
let me stay
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consistent with the colors.
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Now let me write the next
parenthesis right there, and
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then inside of it, we'd evaluate
this first. Let me
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close the parenthesis
right there.
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And then we have plus 44.
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So what is this thing right here
evaluate to, this thing
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inside the parentheses?
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Well, you might be tempted
to say, well, let me
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just go left to right.
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6 plus 10 is 16 and then
divide by 2 and
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you would get 8.
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But remember: order
of operations.
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Division takes priority over
addition, so you actually want
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to do the division first, and
we could actually write it
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here like this.
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You could imagine putting
some more parentheses.
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Let me do it in that
same purple.
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You could imagine putting some
more parentheses right here to
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really emphasize the fact that
you're going to do the
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division first.
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So 10 divided by 2 is 5, so this
will result in 6, plus 10
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divided by 2, is 5.
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6 plus 5.
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Well, we still have to evaluate
this parentheses, so
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this results-- what's
6 plus 5?
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Well, that's 11.
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So we're left with
the 20-- let me
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write it all down again.
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We're left with 8 plus
20 minus 6 plus 5,
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which is 11, plus 44.
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And now that we have everything
at this level of
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operations, we can just
go left to right.
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So 8 plus 20 is 28, so you
can view this as 28
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minus 11 plus 44.
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28 minus 11-- 28 minus 10
would be 18, so this
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is going to be 17.
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It's going to be 17 plus 44.
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And then 17 plus 44-- I'll
scroll down a little bit.
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7 plus 44 would be 51, so
this is going to be 61.
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So this is going to
be equal to 61.
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And we're done!
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