Question

S=1/1*3+1/3*5+1/5*7+.....+1/(2x-1)*(2x+1)
/=supra
*= ori​

Answer 1

Răspuns:

R

Explicație pas cu pas:

S=1/1*3+1/3*5+1/5*7+.....+1/(2x-1)*(2x+1)

3=1+2

5/3=(3+2)/3=1+2/3

7/5=1+2/5

(2x+1)/(2x-1)=[(2x-1)+1+1]/2x-1)=1+2/(2x-1)

S=1+2+1+2/3+1+2/5+1+2/7+1+...+1+2/(2x-1)

S=2+2[1/1+1/3+1/5+1/7+...+1/(2x-1)+2x-1]