{"result":{"text":"T h e space s e r i e s space i s space minus space sum from r equals 0 to 11 of fraction numerator blank to the power of 11 C subscript r left parenthesis negative 2 right parenthesis to the power of r plus 1 end exponent over denominator left parenthesis r plus 1 right parenthesis left parenthesis r plus 2 right parenthesis end fraction equals negative fraction numerator 1 over denominator left parenthesis negative 2 right parenthesis 12 cross times 13 end fraction sum from r equals 0 to 11 of C presuperscript 13 subscript r plus 2 end subscript left parenthesis negative 2 right parenthesis to the power of r plus 2 end exponent\nequals fraction numerator 1 over denominator 2 cross times 12 cross times 13 end fraction left square bracket left parenthesis 1 minus 2 right parenthesis to the power of 13 minus C presuperscript 13 subscript 0 minus 13 left parenthesis negative 2 right parenthesis right square bracket equals fraction numerator 1 over denominator 2 cross times 12 cross times 13 end fraction cross times 24 equals 1 over 13"},"status":"ok"}