Question

Dau coroanã Si 30puncte

Answer 1

Răspuns:

Explicație pas cu pas:

h)S=1/2014-1/2015+1/2015-1/2016+1/2016-1/2017-1/2017=1/2014

i) 22011/11(1/9+1/8+1/7):9x8x7/9x8x7=

2001(9x8+9x7+8x7)/9x8x7·9x8x7/(9x8+9x7+8x7)=2001

j)  progresie geometrica cu q=1/2

(1-1/2-1/2²-.......-1/2^2017)x2^2018=

=[1-1/2(1/2^2017-1)/(1/2-1)]x2^2018=[1-1+2^(-2017)]x2^2018=2^(-2017)]x2^2018=

k) 3+2+1/2+2+1/3+....+2+1/30-(1+1/2+1/3+......+1/30)=

2+2x30+1/2+1/3+...+1/30-(1+1/2+1/3+......+1/30)=2+60=62

=2