a)
[tex] \frac{200 \times 201}{2} = 20.100[/tex]
b)
[tex]3(1 + 2 + 3 + ... + 100)[/tex]
[tex]3( \frac{100 \times 101}{2} ) = 15.150[/tex]
c)
[tex](1 + 2 + 3 + ... + 100) - (1 + 2 + ... + 21)[/tex]
[tex]5.050 - \frac{21 \times 22}{2} [/tex]
[tex]5.050 - 231 = 4.819[/tex]
d)
[tex]1 + 2 + 3 + ... + 302 - (2 + 4 + ... + 302)[/tex]
[tex] \frac{302 \times 303}{2} - 2( 1 + 2 + ... + 151)[/tex]
[tex]45.753 - 2( \frac{151 \times 152}{2} )[/tex]
[tex]45.753 - 22.952 = 22.801[/tex]
Coroniță plsss
