You HAVE to use Pemdas.
2[3(4^2+1)]-2^3
2(3(16+1))-2^3
2(3(17))-2^3
2*51-2^3
102-8
94.
Explanation: you use Pemdas P-parenthesis
E-exponents
M-multiplication
D-division
A-addition
S-subtraction
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