Question

2^2+2^3+2^4=? *
1 point
A) 2^24
B) 2^-5
C) 2^9
D) 2^-9
it's urgent please answer the question please​

Answer 1

Answer:

$using \: formula \\ {2}^{0} + {2}^{1} + ...... + {2}^{n} = {2}^{n + 1} - 1 \\ we \: know \: that \: n = 4 \\ {2}^{0} + {2}^{1} + {2}^{2} + {2}^{3} + {2}^{4} = {2}^{5} - 1 \\ = 32 - 1 = 31 \\ but \: question \: ask \: \\ {2}^{2} + {2}^{3} + {2}^{4} = 31 - {2}^{0} - {2}^{1} \\ = 31 - 1 - 2 = 28$