holds for all real numbers 
.
. 
3. In an arithmetic sequence, the di fference of consecutive terms in constant. We consider sequences of integers in which the di fference of consecutive terms equals the sum of the differences of all preceding consecutive terms.
Which of these sequences with 
and 
contain square numbers?
and contain square numbers? 4. In a triangle 
, let 
, 
and 
denote the base points of the altitudes on the sides 
, 
and 
, respectively.
, let , and denote the base points of the altitudes on the sides , and , respectively.Determine for which triangles two of the lengths 
, 
and 
are equal.
two of the lengths , and are equal.Kάντε κλικ εδώ, για να κατεβάσετε τα θέματα.
