Question

Tìm x, biết:

a) (x + 1) + (x + 2) + (x + 3) + ... + (x + 100) = 205550

b) 3^x + 3^{x + 1} + 3^{x + 2} = 351

Answer 1

a)(x+x+x+...+x)+(1+2+3+...+100)=205550

100x + 5050 =205550

100x =205550 - 5050

100x =200500

x =200500 : 100

x =2005

Answer 2

b)\(3^{x^{ }}+3^{x^{ }}.3+3_{^{ }^{ }^{ }}^{^{ }x}.3^{2^{ }}=351\)

\(3^{x^{ }}\left(1+3+9\right)\)=351

\(3^x\) =351:13

\(3^x\) =27=\(3^3\)

\(\Rightarrow\) x= 3

Answer 3

b)

=351

=351:13

=27=

x= 3

Answer 4

Bát Muội34 phút trước

a)(x+x+x+...+x)+(1+2+3+...+100)=205550

100x + 5050 =205550

100x =205550 - 5050

100x =200500

x =200500 : 100

x =2005

Answer 5

Thanks m.n!