#" "#
Given: #color(blue)([-15w^0u^-1]/[5u^3]#
#color(green)("Step 1 : "#
Exponent Rule: #color(red)(m^0=1#
So, #color(blue)(w^0=1#
Exponent Rule: #color(red)(m^-n=1/m^n#
So, #color(blue)(u^-1=1/u^1=1/u#
#color(green)("Step 2 : "#
Consider: #color(blue)([-15w^0u^-1]/[5u^3]#
To simplify, use the intermediate results found in Step 1:
#rArr [-15(1)(1)]/[5u^3*u]#
Exponent Rule: #color(red)(a^m*a^n=a^(m+n)#
So, #u^3*u=u^3*u^1=u^4#
#rArr -[15]/[5u^4]#
#color(green)("Step 3 : "#
Combine #color(red)("Like Terms"# to simplify
#rArr -(15/5)*(1/u^4)#
#rArr -(cancel 15^color(blue)(3)/cancel 5)*(1/u^4)#
#rArr -3*(1/u^4)#
#rArr -3/u^4#
Hence,
#color(blue)([-15w^0u^-1]/[5u^3] =-(3)/(u^4)#