Question

Tính Tổng:

S=(-2)⁰+(-2)¹+(-2)²+...........+(-2)²⁰¹⁴+(-2)²⁰¹⁵

^{help me :))}

^{giúp mình đi,đây là câu hòi cuối cúng mình duk gừi trong hôm nay}

Answer 1

<=>S=1+(-2)+2^2+....+2^2014+(-2)^2015

=>2S=2.1+(-2.2)+2.2^2+...+2.2^2014+(-2.2)^2015

=>2S=2+2^2+2^3+....+2^2015+2016

=>2S-S=(2+2^2+2^3+....+2^2015+2016)-(1+(-2)+2^2+....+2^2014+(-2)^2015)

=>S=2^2015-1

Answer 2

kho..................lam............................tich,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,minh..........................troi........................ret............................wa.................ung ho minh.................hu....................hu..............hu................hat..............hat....................s