NanoMathematics
In (f ∘ g)(x), apply g first, then put its output into f. The order matters: reversing it usually changes the result.
Function composition: which function comes first?Learning library
Worked questions in maths, physics and chemistry
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Physics
For a constant-mass object in an inertial frame, acceleration depends on the net force. Add the forces with their directions before dividing by mass.
Newton’s second law: find acceleration from net forceChemistry
Conserve the number of atoms of each element by changing the coefficients before formulas. Changing a subscript changes the substance itself.
Balance chemical equations without changing formulasBefore you begin
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