Calc 2 Notes ● Product Rule: (f g)′ = f ′g + f g ′ ( )′ = f g ● f ′g−f g ′ g2 sin(cos−1 x) = √1 − x2 ● Quotient Rule: ● Dx ln u = u1 Dx u sec(tan−1 x) = √1 + x2 ● ∫ u1 du = ln |u| + C tan(sec−1 x) = √x2 − 1, if x ≥ 1 ● ln1=0 cos(sin−1 x) = √1 − x2 − √x2 − 1, if x ≤− 1 Dx sinu = cosu · u′ Dx cosu =− sinu · u′ ln ab =ln a +ln b ln ba =ln a -ln b ● Dx tanu = sec2 u · u′ ln ar = r ln a Logarithmic differentiation helps with a/b or a · b. exists and has an inverse. 1 (f )′(y) = f (x) ′ If f ′(x) =/ 0 , f ● ● −1 elnx = x u ln(ex ) = x u ∫ eu du ● Dx e = e Dx u ● ln (ax ) = ln (exlna ) = x ln a y ax ay = ax+y (ax ) = axy ● x ( ab ) = x (ab) = ax bx ● Dx secu = secutanu · u′ Dx cscu =− cscucotu · u′ ● −1 = eu 1 · u′, − 1 ≺ u ≺ 1 √1−u2 Dx cos−1 u =− 1 2 · u′, − 1 ≺ u ≺ 1 √1−u 1 −1 Dx tan u = 1+u2 · u′ Dx sin−1 u = Dx sec−1 u = +C ● 2 2 Dx au = au ln a · Dx u 2 ● xx = exlnx Dx = exlnx DX (xlnx) ● = x · 1x + lnx log a x = lna ● ( ∫ xa dx = xx (1 + lnx) lnx) = 1 Dx log a x = xlna x +C a+1 ● dy Exponential Growth/Decay: dt = dT Newton Cooling: dt = k (T − T 1 ) Continuous: ● ● a+1 Compound Interest: ert x = sin−1 y ⇔ y = sinx, y = y 0 ekt ky A(t) = A0 (1 + A(t) = A0 −π 2 ≤x≤ −π 2 ≤x≤ π 2 x = sec−1 y ⇔ y = secx, 0 ≤ x ≤ π, x =/ 2 1 −1 a sec ex −e−x 2 sinhx tanhx = coshx 1 sechx = coshx |x| a coshx = sinhx = 2 ( )+C cothx = cschx = 2 ex +e−x 2 coshx sinhx 1 sinhx cosh x − sinh x = 1 Dx sinhu = coshu · u′ Dx coshu = sinhu · u′ Dx tanhu = sech2 u · u′ DX cothu =− csch2 u · u′ Dx sechu =− sechutanhu · u′ r nt ) n Dx cschu =− cschucothu · u′ π 2 x = cos−1 y ⇔ y = cosx, 0 ≤ x ≤ π x = tan−1 y ⇔ y = tanx, dx = a1 tan−1 ( ax) + C ∫ x√x1−a dx = ● · u′, |u| ≻ 1 2 2 xx 1 |u|√u2 −1 ∫ √a1−x dx = sin−1 ( ax) + C 1 ∫ a +x ax bx 1 ∫ ax dx = ( lna ) ax + C Dx cotu =− csc2 u · u′ π 2 Absolute Value Derivative: |u(x)|’ = [ u(x) / |u(x)| ]*u’(x) ● Dx sinh−1 x = 1 √x2 +1 Dx cosh−1 x = 1 , x≻1 √x2 −1 1 Dx tanh−1 x = 1−x 2, − 1 ≺ x ≺ 1 Dx sech−1 x = −1 , x√1−x2 0≺x≺1 Trig Identities First-Order Linear EQ: dy dx + P (x)y = Q(x) Reciprocals: ∫ P (x)dx 1)Find Integrating Factor e 2) Multiply both sides by e 1 sinu = cscu 1 tanu = cotu ∫ P (x)dx Pythagorean Identities: sin2 u + cos2 u = 1 1 + tan2 u = sec2 u 3) The equation becomes: ∫ P (x)dx dy dx e ∫ P (x)dx +e ∫ P (x)dx P (x)y = e 4)Left side is the derivative of the product So the equation becomes: ∫ P (x)dx d dx y·e ∫ P (x)dx =e 1 cosu = secu Q(x) ∫ P (x)dx y·e 1 + cot2 u = csc2 u Quotients: sinu tanu = cosu cotu = cosu sinu Sum/Difference Formulas: sin(u + v ) = sinucosv + cosusinv sin(u − v ) = sinucosv − cosusinv Q(x) cos(u + v ) = cosucosv − sinusinv cos(u − v ) = cosucosv + sinusinv tanu+tanv tan(u + v ) = 1−tanutanv 5) Integrate both sides: ∫ P (x)dx ye ∫ P (x)dx = ∫ Q(x)e dx −∫ P (x)dx ∫ Double Angle Formulas: sin(2u) = 2sinucosu 6) Solution is: y=e tanu−tanv tan(u + v ) = 1+tanutanv cos(2u) = cos2 u − sin2 u ∫ P (x)dx Q(x)e dx = 2cos2 u − 1 = 1 − 2sin2 u 2tanu tan(2u) = 1−tan 2u