The side of a cube is decreasing at a rate of 9 millimeters per minute.At a certain instant, the side is 19 millimeters.What is the rate of change of the volume of the cube at that instant (in cubic millimeters per minute)?Choose 1 answer:(A) −729(B) −9747(C) −6859(D) −3249
Q. The side of a cube is decreasing at a rate of 9 millimeters per minute.At a certain instant, the side is 19 millimeters.What is the rate of change of the volume of the cube at that instant (in cubic millimeters per minute)?Choose 1 answer:(A) −729(B) −9747(C) −6859(D) −3249
Volume formula: Volume of a cube formula is V=s3, where s is the side length.
Differentiate volume: Differentiate the volume with respect to time to find the rate of change of volume, dtdV=3s2⋅dtds.
Plug in values: Plug in the values: s=19mm and dtds=−9mm/min.
Calculate dtdV: Calculate dtdV=3×(19)2×(−9).
Simplify calculation: Simplify the calculation: dtdV=3×361×(−9).
Multiply for rate: Multiply to find the rate of change: dtdV=3×361×(−9)=1083×(−9).
Final calculation: Final calculation: dtdV=−9747mm3/min.
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