Pls answer the 8 th question pls

Answer:
The simplified expression is:
[tex]\dfrac{-7}{10}p^2q^2r+\dfrac{1}{2}pq^2r-\dfrac{11}{28}pqr^2+\dfrac{1}{8}p^2qr[/tex]
Step-by-step explanation:
To find:
[tex]-\dfrac{1}{2}p^{2} q^{2} r+\dfrac{1}{3}p q^{2} r-\dfrac{1}{4}p q r^{2}-\dfrac{1}{5}rq^{2} p^{2} +\dfrac{1}{6}rq^{2} p-\dfrac{1}{7}r^{2}pq+\dfrac{1}{8}rp^{2}q[/tex]
Solution:
We can see that pqr having power 1 is common throughout.
Let us take it common to make the expression simpler and then we will add by taking LCM:
[tex]\Rightarrow pqr(-\dfrac{1}{2}p q+\dfrac{1}{3}q-\dfrac{1}{4}r-\dfrac{1}{5}pq+\dfrac{1}{6}q-\dfrac{1}{7}r+\dfrac{1}{8}p)\\\Rightarrow pqr(-\dfrac{1}{2}p q-\dfrac{1}{5}pq+\dfrac{1}{3}q+\dfrac{1}{6}q-\dfrac{1}{4}r-\dfrac{1}{7}r+\dfrac{1}{8}p)\\\Rightarrow pqr(\dfrac{-5pq-2pq}{2\times 5}+\dfrac{2q+q}{2 \times 3}+\dfrac{-7r-4r}{7 \times 4}+\dfrac{1}{8}p)\\\Rightarrow pqr(\dfrac{-7pq}{10}+\dfrac{3q}{6}+\dfrac{-11r}{28}+\dfrac{1}{8}p)\\\Rightarrow pqr(\dfrac{-7}{10}pq+\dfrac{1}{2}q+\dfrac{-11}{28}r+\dfrac{1}{8}p)[/tex]
Now, multiplying pqr again to the expression:
[tex]\Rightarrow \dfrac{-7}{10}p^2q^2r+\dfrac{1}{2}pq^2r-\dfrac{11}{28}pqr^2+\dfrac{1}{8}p^2qr[/tex]
So, the answer is:
[tex]\dfrac{-7}{10}p^2q^2r+\dfrac{1}{2}pq^2r-\dfrac{11}{28}pqr^2+\dfrac{1}{8}p^2qr[/tex]