Past Papers’ Solutions | Cambridge International Examinations (CIE) | AS & A level | Mathematics 9709 | Pure Mathematics 1 (P1-9709/01) | Year 2016 | Feb-Mar | (P1-9709/12) | Q#4
Question
a. Solve the equation , giving the solution in an exact form.
b. Solve, by factorising, the equation for
.
Solution
a.
We are given;
b.
We are required to solve, by factorising, the following equation for .
Now we have two options.
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We utilize the periodic property of to find other solutions (roots) of
:
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Symmetry |
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Hence;
Therefore, another solution of is
but it is outside desired limit
, so we can ignore it.
Since our limits of interest are , we need not to use periodic property of
because that will result in solutions outside limits of interest.
We utilize the periodic property of to find another solution (root) of
:
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Symmetry |
Or |
Hence;
Therefore, we have only one solution for
.
Since our limits of interest are , we need not to use periodic property of
because that will result in solutions outside limits of interest.
Hence there are only two solutions of for
.
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