Efectuati:a)(-1)la puterea1+(-1) la puterea (-1)la puterea3+........+(-1)la puterea51= b)(-1)la puterea1x(-1)la puterea2x......x(-1)la puterea 51= c)4+2 la puterea2+2 la puterea3+......+2 la puterea10= d)-2-(-2)la puterea2+(-2)la puterea3-.....+(-2)la puterea9-(-2)la puterea10= e)(-1)la puterea k+1 +(-1)la puterea k,k apartine multimii N
a) (-1)^(2k+1)= -1 -1-1.....-1= - 26 (sunt 26 de termeni egali) b) (-1)^2k=1 -1*1*(-1)*1*..........*(-1)*1 = 1 (sunt 26 de factori negativi ) c) 4+2^2+2^3+.....+2^10=1+2^0+2^1+2^2+....+2^10=1+2^11-1=2^11
