import math
x=float(input( ))
b=float(input( ))
a=float(input( ))
if(b!=0):
if(x<a/b):
y=a*math.power(math.cos(math.power(x,3)),2)+b*math.sin(x)
print("y=",y)
elif(x>ab):
y=2.8*math.power(a,2)+(math.power(b,2)-math.power(x,2))
print("y=",y)
else:
y=a*math.tan(a*x+math.power(b,2))
print("y=",y)
else:
print("ERROR! b=0")
# your code goes here
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