Q. Solve the equation.dxdy=−41exy−2Choose 1 answer:(A) y=±3−43ex+C(B) y=3−43ex+C(C) y=±3−43ex+C(D) y=3−43ex+C
Separate variables: We are given the differential equation (dxdy=−41exy−2). This is a separable differential equation, which means we can separate the variables y and x on different sides of the equation.
Multiply and integrate: To separate the variables, we multiply both sides by y2 and dx to get y2dy=−41exdx.
Integrate both sides: Now we integrate both sides of the equation. The left side with respect to y, and the right side with respect to x.∫y2dy=∫−(41)exdx
Simplify and rename constant: The integral of y2 with respect to y is (1/3)y3. The integral of −(1/4)ex with respect to x is −(1/4)ex. So we have:(1/3)y3=−(1/4)ex+C, where C is the constant of integration.
Take cube root: We multiply through by 3 to get rid of the fraction on the left side:y3=−(43)ex+3CWe can rename 3C as a new constant, let's call it C′:y3=−(43)ex+C′
Final solution: To solve for y, we take the cube root of both sides:y=±3−(43)ex+C′This matches answer choice (A), which is y=±3−(43ex)+C.
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