x+y=e^(π/2).
詳解一,對(duì)數(shù)螺線方程ρ=e^θ在點(diǎn)θ=π/2處的切線直角坐標(biāo)系方程見(jiàn)附圖;
詳解二:
對(duì)數(shù)螺線方程ρ=e^θ可化為隱函數(shù)方程:
ln√[x^2+y^2]=arctan(y/x),
利用隱函數(shù)求導(dǎo)法,求得在點(diǎn)[0,e^(π/2)]處的導(dǎo)數(shù)為y'(0)=-1,
故 所求在點(diǎn)(ρ,θ)處的切線方程是:
y-e^(π/2)=-1(x-0)=-x,
即 x+y=e^(π/2).
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