Processing Math: Done

From Förberedande kurs i matematik 1

Method 1

One solution is to calculate the numerator and denominator in the main fraction individually

21+3131−21=2313+3212=63+62=65=3212−2313=62−63=−61.

The whole expression then reduces to a double fraction which we calculate by multiplying top and bottom by the reciprocal of the denominator

31−2121+31=65−61=656−616=5−1=−5

Method 2

Another way to solve the exercise is to multiply the top and bottom of the main fraction by 32=6, so that all denominators in the partial fractions 1/2 and 1/3 can eliminated in one step

31−2121+31=31−21621+316=36−2626+36=2−33+2=5−1=−5.