To find the minimum temperature, we must consider the graph of T (t). Note that T (t) is a transformed sine function, specifically

is related graphically to the function y = f (t) = sint through the following transformations (in order):

1. Vertically stretched by a factor of 1.3,
2. Horizontally shifted left 2 units,
3. Horizontally stretched by a factor of 12/π,
4. Reflected across the y-axis (in this case the T-axis),
5. Shifted up by 36.8 units.

Because the graph is shifted up 36.8 units and has an amplitude of 1.3 units, we know that T(t) has a maximum of 36.8 + 1.3 = 38.1°C and a minimum of 36.8 - 1.3 = 35.5 °C.

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