Page 28 - More Higher algebra
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log ( ) = − log (2 + 1)
4
4
−1
log ( ) = log (2 + 1)
4
4
Remove logs
1
=
2 + 1
This can be written as.
(2 + 1) = 1
or
2
2 + − 1 = 0
This factorises to give,
(2 − 1)( + 1)
There are two solutions, x = ½ and -1, however the last
solution must be ignored (log of negative number).
Verify the results by using SOLVE on your fx calculator,
log ( ) + log (2 + 1) = 0
4
4
The keystrokes for this expression are,
Ci4$Q(X)$+i4$2J(X)
+1$Q(=)0q(SOLVE)
Seed for the algorithm x = 4,
24
