關於微積分的公式 - 學習

consider this triangle


/|
√(1+x^2) / | x
/ _|
/θ||

1

1 x
so, cosθ = --------- sinθ = --------- tanθ = x
√(1+x^2) √(1+x^2)


and then, use them to solve triangle integral problems.

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