基本の微分(d/dt)
- d(t^n)/dt = n*t^(n-1)
- d(e^t)/dt = e^t
- d(a^t)/dt = a^t*ln(a)
- d(ln t)/dt = 1/t
- d(sin t)/dt = cos t
- d(cos t)/dt = -sin t
- d(tan t)/dt = sec^2 t
- d(cot t)/dt = -csc^2 t
- d(sec t)/dt = sec t * tan t
- d(csc t)/dt = -csc t * cot t
⸻
合成関数(チェーンルール)
- d(f(g(t)))/dt = f’(g(t))*g’(t)
- d(sin(at))/dt = a*cos(at)
- d(cos(at))/dt = -a*sin(at)
- d(e^(at))/dt = a*e^(at)
- d(ln(at))/dt = 1/t
⸻
積分(∫ dt)
- ∫ t^n dt = t^(n+1)/(n+1) + C (n≠-1)
- ∫ 1/t dt = ln|t| + C
- ∫ e^t dt = e^t + C
- ∫ a^t dt = a^t / ln a + C
- ∫ sin t dt = -cos t + C
- ∫ cos t dt = sin t + C
- ∫ sec^2 t dt = tan t + C
- ∫ csc^2 t dt = -cot t + C
- ∫ sec t * tan t dt = sec t + C
- ∫ csc t * cot t dt = -csc t + C
⸻
定積分(0→T)
- ∫_0^T t dt = T^2/2
- ∫_0^T t^2 dt = T^3/3
- ∫_0^T e^t dt = e^T - 1
- ∫_0^T sin t dt = 1 - cos T
- ∫_0^T cos t dt = sin T
⸻
運動の基本(時間 t 秒)
- v(t) = dx/dt
- a(t) = dv/dt
- x(t) = ∫ v(t) dt
- v(t) = ∫ a(t) dt
- F(t) = m*a(t)
- p(t) = m*v(t)
- W = ∫ F(t)*v(t) dt
- KE = 1/2 m*v(t)^2
- P(t) = dW/dt
- Momentum = ∫ F dt
⸻
指数・対数関数
- d/dt (e^(kt)) = k e^(kt)
- ∫ e^(kt) dt = (1/k) e^(kt) + C
- d/dt (ln(1+t)) = 1/(1+t)
- ∫ 1/(1+t) dt = ln(1+t)
- d/dt (a^(bt)) = b*ln(a)*a^(bt)
⸻
三角関数の積分
- ∫ sin(at) dt = -1/a cos(at) + C
- ∫ cos(at) dt = 1/a sin(at) + C
- ∫ tan t dt = -ln|cos t| + C
- ∫ cot t dt = ln|sin t| + C
- ∫ sec t dt = ln|sec t + tan t| + C
- ∫ csc t dt = -ln|csc t + cot t| + C
⸻
双曲線関数
- d(sinh t)/dt = cosh t
- d(cosh t)/dt = sinh t
- d(tanh t)/dt = sech^2 t
- ∫ sinh t dt = cosh t + C
- ∫ cosh t dt = sinh t + C
⸻
物理的応用
- Q(t) = ∫ I(t) dt (電気量)
- V(t) = L dI/dt (インダクタンス)
- I(t) = C dV/dt (コンデンサ)
- Energy = ∫ P(t) dt
- ω(t) = dθ/dt (角速度)
- α(t) = dω/dt (角加速度)
- θ(t) = ∫ ω(t) dt
- Work = ∫ F(t) dx
- Impulse = ∫ F(t) dt
⸻
フーリエ系
- ∫_0^T sin(nωt) dt = (1 - cos(nωT))/(nω)
- ∫_0^T cos(nωt) dt = sin(nωT)/(nω)
- d/dt (sin ωt + cos ωt) = ω(cos ωt - sin ωt)
- Parseval’s theorem (time domain integration)
⸻
高次導関数
- d^2x/dt^2 = acceleration
- d^2y/dt^2 = curvature in motion
- d^3x/dt^3 = jerk
- d^4x/dt^4 = snap
- d^5x/dt^5 = crackle
- d^6x/dt^6 = pop
⸻
ラプラス変換(時間 t 秒)
- L{1} = 1/s
- L{t} = 1/s^2
- L{e^(at)} = 1/(s-a)
- L{sin at} = a/(s^2 + a^2)
- L{cos at} = s/(s^2 + a^2)
⸻
確率・統計応用
- E[X(t)] = ∫ x f(x,t) dx
- Var[X(t)] = E[X^2] - (E[X])^2
- ∫_0^∞ e^(-λt) dt = 1/λ
⸻
エネルギー系
- KE(t) = ∫ F(t)*v(t) dt
- PE(t) = ∫ F(t) dx
- E_total = KE + PE
- Heat Q = ∫ I^2 R dt
⸻
数列・和の極限を微積に
- lim_{Δt→0} (Δx/Δt) = dx/dt
- ∑ f(t) Δt → ∫ f(t) dt
- Average value: (1/T) ∫_0^T f(t) dt
⸻
高校~大学基礎の代表
- d/dt (f(t)g(t)) = f’g + fg’
- d/dt (f/g) = (f’g - fg’)/g^2
- ∫ f’(t)/f(t) dt = ln|f(t)| + C
- ∫ e^(at)cos(bt) dt = e^(at)(a cos bt + b sin bt)/(a^2+b^2)
- ∫ e^(at)sin(bt) dt = e^(at)(a sin bt - b cos bt)/(a^2+b^2)
⸻
まとめ(100に調整)
- Taylor展開: f(t) ≈ f(0) + f’(0)t + f’’(0)t^2/2 + ...
- Maclaurin: e^t = 1 + t + t^2/2! + ...
- ∫_0^∞ e^(-at) dt = 1/a
- δ(t): ∫ δ(t) f(t) dt = f(0)
- Heaviside H(t): dH/dt = δ(t)
⸻