Find the remainder of the equation

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The discussion focuses on finding the remainder of the equation \(\frac{18^2 + 2^{100}}{11}\). The user successfully calculates that \(18^2 \equiv 5 \,(\text{mod}\, 11)\) but struggles with \(2^{100}\). They inquire about using modular arithmetic properties, specifically \(a \equiv b \,(\text{mod}\, m) \Rightarrow a^k \equiv b^k \,(\text{mod}\, m)\), to simplify the calculation of \(d\). The conversation emphasizes the application of modular arithmetic to solve complex equations efficiently.

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parsifal
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The task is to find the remainder of the equation:
\frac{18^2+2^{100}}{11}

Now I know that if
a \equiv b\ (mod\ m),\ c \equiv d\ (mod\ m) \Rightarrow
a + c \equiv b +d\ (mod\ m) and ac \equiv bd\ (mod\ m)

so

18^2 \equiv b\ (mod\ 11) \Rightarrow \frac{18^2}{11}=29.454545... \Rightarrow b=18^2-11\cdot 29=5
and d<6 as the remainder b+d < 11.

But as 2^100 is so large, I can't find d the way I found b. How to find it, or is there some other more convenient way that doesn't involve separating 18^2 and 2^100?
 
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have you tried using this a\equiv b (\text{mod}\; m) \Rightarrow a^k\equiv b^k (\text{mod}\; m) to help?

The answer should be obvious after the use of this theorem
 

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