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RedPen
Fifty confident, neat, wrong derivations in algebra, calculus, mechanics, chemistry and statistics. Find the first line that fails, pick the corrected line, and name the kind of failure: algebra slip, wrong principle, unit error or unjustified step. Answers are cheap now; checking is the skill. Every line is checked by an exact engine, and nothing leaves your device.
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Learning goal
Fifty confident, neat, wrong derivations in algebra, calculus, mechanics, chemistry and statistics. Find the first line that fails, pick the corrected line, and name the kind of failure: algebra slip, wrong principle, unit error or unjustified step. Answers are cheap now; checking is the skill. Every line is checked by an exact engine, and nothing leaves your device.
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