dy/ cos^2( ay) = dx where a = pi/4
integral dy/cos^2 (ay) = (1/a) tan ay from integral table
so
x = (4/pi) tan pi y/4 + c
0 = (4/pi) tan pi/4 + c
but tan (pi/4) = 1
so
c = -4/pi
and
x = (4/pi) tan pi y/4 - 4/pi = (4/pi) (tan pi y/4 -1)
now put in y = 3
looks like about -8/pi
If dy/dx=cos^2(πy/4) and y=1 when x=0, then find the value of x when y=3
a) 1/8
b) -π/8
c) -8/π
d) None of these
1 answer
1 answer