Find the differential dy

Question

Let y=tan(5x+6).
Find the differential dy when x=4 and dx=0.4
Find the differential dy when x=4 and dx=0.8

Answer 1

dy=5*sec²(5x+6)dy

 

put x=4 and dx=.4 in the above and calculate. sec(θ)=1/cos(θ)

 

for the second part change dx from .4 to .8

 

Jim