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中文
tex equatiaon test

a=b+cb=c+d(1)a = b+c \\ b = c+d \tag{1}

fY(y)=fX[h(y)]h(y)=fX[h(y)]h(y)=1θexθ[dxdy(θln(1y))]=1θeθln(1y)θθ1y=1θeln(1y)θ1y=1yθθ1y=1\begin{aligned} f_Y(y) & = f_X[h(y)]|h'(y)| \\[2ex] & = f_X[h(y)]h'(y) \\[2ex] & = \frac{1}{\theta}e^{-\frac{x}{\theta}}[\frac{dx}{dy}(-\frac{\theta}{ln(1-y)})] \\[2ex] & = \frac{1}{\theta}e^{-\frac{-\frac{\theta}{ln(1-y)}}{\theta}}\frac{\theta}{1-y} \\[2ex] & = \frac{1}{\theta}e^{ln(1-y)}\frac{\theta}{1-y} \\[2ex] & = \frac{1-y}{\theta}\frac{\theta}{1-y} \\[2ex] & = 1 \end{aligned}

inline equatiaon ab\frac{a}{b}

Hera is a figure.

你好像进退两难...