WAEC - Mathematics (2021 - No. 12)
Simplify 2√7- \(\frac{14}{√7} + \frac{7}{√21}\)
\(\frac{√21}{21}\)
7\(\frac{√21}{21}\)
\(\frac{√21}{3}\)
3√21
설명
2√7- \(\frac{14}{√7} + \frac{7}{√21}\)
L.C.M is √21
\(\frac{√21 * 2√7 - √3 *14 + 7}{√21}\)
=\(\frac{2 * 7√3 - 14√3 + 7}{√21}\)
= \(\frac{14√3 - 14√3 + 7}{√21}\)
=\(\frac{7}{√21}\)
or
\(\frac{7 \times √21}{√21 \times √21}\)
= \(\frac{7 \times √21}{21}\) or \(\frac{√21}{3}\)