Anastasia tried to solve the differential equation dxdy=y2sin(x). This is her work:dxdy=y2sin(x)Step 1: ∫y2dy=∫sin(x)dxStep 2: 3y3=−cos(x)+C1Step 3: y3=−3cos(x)+CStep 4: y=3−3cos(x)+CIs Anastasia's work correct? If not, what is her mistake?Choose 1 answer:(A) Anastasia's work is correct.(B) Step 1 is incorrect. The separation of variables wasn't done correctly.(C) Step 2 is incorrect. Anastasia didn't integrate sin(x) correctly.(D) Step 4 is incorrect. The right-hand side of the equation should be 3−cos(x)+C.
Q. Anastasia tried to solve the differential equation dxdy=y2sin(x). This is her work:dxdy=y2sin(x)Step 1: ∫y2dy=∫sin(x)dxStep 2: 3y3=−cos(x)+C1Step 3: y3=−3cos(x)+CStep 4: y=3−3cos(x)+CIs Anastasia's work correct? If not, what is her mistake?Choose 1 answer:(A) Anastasia's work is correct.(B) Step 1 is incorrect. The separation of variables wasn't done correctly.(C) Step 2 is incorrect. Anastasia didn't integrate sin(x) correctly.(D) Step 4 is incorrect. The right-hand side of the equation should be 3−cos(x)+C.
Separating Variables: Anastasia starts by separating variables.(dxdy)=y2sin(x)To separate variables, we need to get all y terms on one side and all x terms on the other side.(y2dy)=sin(x)dxThis is the correct separation of variables.
Integrating Both Sides: Anastasia integrates both sides.∫(1/y2)dy=∫sin(x)dxThe integral of 1/y2 with respect to y is −1/y, and the integral of sin(x) with respect to x is −cos(x).So, −1/y=−cos(x)+C1Anastasia's integration result is incorrect.
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