If $p( a ) = 6a ^ { 3} - 20a - 10$ , what is $p ( - 6) and p ( \frac { 1} { 6} )$ ?

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Answer 1 · 2017-12-02T01:18:00

$p(-6)=-1196$

$p(\frac{1}{6})=-\frac{479}{36}$ or $-13\frac{11}{36}$

To find the values of $p(-6)$ and $p(1/6)$ , we just need to plug those values into the function $6a^3-20a-10$ for $a$ .

Let’s plug in $-6$ for $p$ first:

$p(a)=6a^3-20a-10$

$\implies p(-6)=6(-6)^3-20(-6)-10$

$\implies p(-6)=6(-216)-(-120)-10$

$\implies p(-6)=-1296+120-10$

$\implies p(-6)=-1176-10$

$\implies p(-6)=-1186$

Now we do the same for $p=\frac{1}{6}$ :

$p(a)=6a^3-20a-10$

$\implies p(\frac{1}{6})=6(\frac{1}{6})^3-20(\frac{1}{6})-10$

$\implies p(\frac{1}{6})=6(\frac{1}{216})-\frac{10}{3}-10$

$\implies p(\frac{1}{6})=\frac{1}{36}-\frac{10}{3}-10$

$\implies p(\frac{1}{6})=\frac{2}{72}-\frac{240}{72}-\frac{720}{72}$

$\implies p(\frac{1}{6})=-\frac{958}{72}$

That can also be expressed as $-13\frac{11}{33}$

If p( a ) = 6a ^ { 3} - 20a - 10p( a ) = 6a ^ { 3} - 20a - 10, what is p ( - 6) and p ( \frac { 1} { 6} )p ( - 6) and p ( \frac { 1} { 6} )?