let y=2x^2 +5x+3

Question

Find the differential dy when x= 5 and dx = 0.1
Find the differential dy when x= 5 and dx = 0.2

Answer 1

dy/dx = 4x + 5
dy = (4x + 5)dx
so for your given data
dy= (20+5)(.1) = 2.5

so the other one the same way