x=1+2+4+8+16+..... x=1+(2+4+8+16.....) x=1+2(x) x=-1 playing LOL = not study not playing LOL= study ㅡㅡㅡㅡㅡㅡㅡㅡㅡ (1+not)(playing LOL) =(not+1)(study) -> playing LOL=study playing lol= 망함
