The order of the differential equation of family of curves y=C1sin−1x+C2cos−1x+C3tan−1x+C4cot−1x(where C1,C2,C3 and C4 are arbitrary constants) is
The order of the differential equation whose general solution is given by y=(c1+c2)cos(x+c3)−c4ex+c5, where c1,c2,c3,c4,c5 are arbitrary constants, is