y = f(secx),f '(x) = x
y ' = f ' (secx) * (secx) ' = secx * secx tanx = sec²x tanx
x->π/2,dy/dx -> ∞感謝您回答 答案是2如果f '(x) = x 必有 f(x) = x² /2 + C (C為一個常數(shù))y = f(secx) = sec²x /2 + Cy ' = secx * secx tanx = sec²x tanx 當(dāng)x=π/4時,dy/dx = 2 。4分之派是什么啊當(dāng)x->π/2時,dy/dx -> ∞; 當(dāng)x=π/4時,dy/dx = 2請檢查題目。