junior college 2 chevron_right H2 Maths chevron_right Singapore

Hi guys, as Newton's law of cooling is application for DE, where its rate of change of temperature is directly proportional to the difference between temperature of surrounding( 30 degree celcius assumed same throughout) and temperature of the object, @. Considering convention wise , d@/dt = -k( @-30) : k is positive. Is it okay if i write d@/ dt = k(30- @) , k is positive but no have - sign in front. Because both sets of DE yield back the same general formula of DE but i not sure if it is accepted.