How do you simplify #(13r^7)/(39r^4)#?

2 Answers
Apr 28, 2017

#(r^3)/3#

Explanation:

You can write down tour equation again:

#(13*r^4*r^3)/(3*13*r^4)#

Now #13r^4#s cancel each other

You get

#r^3/13#

This is your answer #r^3/13#

Apr 28, 2017

#(13r^3)/39#

Explanation:

#color(blue)("First principle method")#

Note that 13 is a prime number so you can not simplify any further the value of #13/39#

Write as: #" "13/39xx(r^4xxr^3)/r^4#

#" "13/39xxr^4/r^4xxr^3#

But #r^4/r^4=1# giving:

#" "13/39xx1xxr^3#

#" "(13r^3)/39#
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(blue)("Shortcut method")#

#(13r^7)/(39r^4)" "=" "(13r^(7-4))/39" "=(13r^3)/39#