Răspuns :
1/√2 + 2/√8 + 3/√18 + 4/√32=
Rationalizam numitorii
1/√2=√2/2
2/√8=2/2√2=1/√2=√2/2
3/√18=3/3√2=1/√2=√2/2
4/√32=4/4√2=1/√2=√2/2
√2/2+√2/2+√2/2+√2/2=4√2/2=2√2 ceea ce era de demonstrat
Rationalizam numitorii
1/√2=√2/2
2/√8=2/2√2=1/√2=√2/2
3/√18=3/3√2=1/√2=√2/2
4/√32=4/4√2=1/√2=√2/2
√2/2+√2/2+√2/2+√2/2=4√2/2=2√2 ceea ce era de demonstrat
a=1/√2+2/√8+3/√18+4/√32= 1/√2+ 2/2√2+ 3/3√2+ 4/4√2= 1/√2+1/√2+ 1/√2+ +1/√2= 1/√2*4=4√2
/*√2
a=4/√2 =4√2/2=2√2
/*√2
a=4/√2 =4√2/2=2√2