WEBVTT
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Evaluate the expression.
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Write down all of the figures on the calculator display.
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Now most scientific calculators will allow us to type this exact calculation in and will apply the order of operations BIDMAS or BODMAS to calculate the answer.
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There are a couple of little quirks to be aware of though.
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To get the square root symbol, we press this button.
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Once we’ve then typed 24.12 multiplied by three, we need to press right on the arrow button.
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That will take us outside of the square root sign, and we’ll be able to carry on the calculation as normal.
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If we type this exact calculation in, we get negative 2.198114554.
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However, we should always write down in between steps to ensure that we don’t lose all the marks should we accidentally type it wrong.
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The first thing we should do is work out the value of the expression inside the square root symbol.
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24.12 multiplied by three gives us 72.36.
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The square root of 72.36 is 8.5064, and so on.
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It is important that we use this exact number in any future calculations.
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If we decided to round at this point and you say 8.5 in our next step, we could lose some accuracy.
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Many calculators have a previous answer button that will allow us to carry this exact number through your calculation.
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Next, we should evaluate the expression inside our brackets on the denominator of the fraction.
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0.29 minus 1.86 is negative 1.57, and negative 1.57 cubed is negative 3.869893 exactly.
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Our final step is to divide the unrounded version of the square root of 72.36 by negative 3.869893.
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And that gives us negative 2.198114554.
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Now a common mistake is not to read the question fully.
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It is telling us to write all the digits on our calculator display.
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So that’s exactly what we should do.
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The answer is negative 2.198114554.