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Simplify two π cubed minus four π squared minus nine plus five π cubed minus three π plus one.
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Before we start this question, it is important to remember two things.
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Firstly, we can only group or collect terms with the same exponent.
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In this question, we can group the two π cubed and the five π cubed and also the negative nine and positive one.
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Thereβs only one π squared term and, likewise, only one π term.
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Therefore, these two terms cannot be simplified.
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It is also important to remember our rules when two signs are touching.
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If we have two positive signs, our resultant sign is an addition.
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A positive and a negative results in a subtraction or negative sign.
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And two negative signs result in a positive or addition sign.
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Grouping the π cubed terms gives us two π cubed plus five π cubed.
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As two plus five is equal to seven, two π cubed plus five π cubed equals seven π cubed.
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As previously mentioned, there is only one π squared and one π term.
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Therefore, negative four π squared and negative three π need to be in the answer.
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Finally, we need to collect the numbers negative nine plus positive one.
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As we have two positive signs touching each other, the resultant sign is positive or addition, leaving us with negative nine plus one.
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This is equal to negative eight.
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The simplified version of two π cubed minus four π squared minus nine plus five π cubed minus three π plus one is seven π cubed minus four π squared minus three π minus eight.