MaxWong

Let x = 1-0.02  This is unnecessary but just for easier understanding.

$\text{Original expression}\\ =\dfrac{2x^{10}}{x}\\ =2x^9\\ \text{Now back-substitute the values.}\\ =2(1-0.02)^9\\ =2\cdot(0.98)^9\\ =2\cdot0.83374776213\\ =1.66749552426$

Welcome back, Guest! :D

$\begin{array}{rll}3^{81x}&=&81^{3x}\\ 81x\cdot \log_33 &=& 3x\cdot\log_381\\ 81x&=&12x\end{array}\\ \mbox{The only solution is }x=0$

2 + 2 = 4, isn't it?

Example:

2.653 x 3.332

estimated: 3 x 3 = 9

actual: 2.653 x 3.332 = 8.839796

Close enough, isn't it?

Multiply 100 to both the numerator and denominator.

$\begin{array}{rl}&\dfrac{1}{1.01}\\=&\dfrac{100}{101}\end{array}$

Exponents smaller than whole number, I bet you mean fractions and negative numbers.

$\boxed{\color{red}m^{\frac{a}{n}}=\sqrt[n]{m^a}}$

$\boxed{\color{red}m^{-n}=\dfrac{1}{m^n}}$