Fatima evaluated the expression StartFraction 4 m Superscript negative 3 Baseline n Superscript negative 2 Baseline Over m Superscript negative 1 Baseline n EndFraction, when m = negative 2 and n = 4. Her work is shown below.
StartFraction 4 m Superscript negative 3 Baseline n Superscript negative 2 Baseline Over m Superscript negative 1 Baseline n EndFraction = 4 m Superscript negative 2 Baseline n Superscript negative 3 Baseline = 4 (negative 2) Superscript negative 2 Baseline (4) Superscript negative 3 Baseline = StartFraction 1 Over 64 EndFraction times StartFraction 1 Over 64 EndFraction = StartFraction 1 Over 4,096 EndFraction
What was Fatima’s error?
She subtracted the exponents incorrectly when simplifying the expression.
She substituted the wrong values for the variables.
She applied the exponent Negative 2 to 4 (negative 2) instead of applying the exponent to just Negative 2.
She found an incorrect value for (Negative 8) Superscript negative 2 since the value should be negative.
7 answers
Use parentheses to disambiguate things until wolfram interprets your expression the way you intend it.
This will not only give you the answer you seek, but will give you practice typing complicated expressions online.