the differential equation of the family of circles with fixed radius r and with centre on y-axis is

1. y²(1+y₁²)=r²y₁²

1. y²=y₁²+r²y₁
2. x²(1+y₁²)=r²y₁²
3. x²=y₁²+r²y₁

the diameter of a roller is 84 cm and its length is 120 cm. it takes 500 complete revolution to  move once over to level a playground. find the area of the playground in square m?

Find dy/DX when y=x^sinx+sin-1√x.

 

Please give me the solution of this problem. 

Solve the differential equation y’’+2ty’-4y=1, y(0)=y’(0)=0.