sorusunun cozumu. arc cosh x=y, cosh y=x (ey +e-y)/2=x, Q=ey tanimi yapalim. Q-1=e-y olur. cosh y=(e +e )/2=x, → (Q+Q )/2=x → Q + y -y -1 1 = 2x Q Q2 + 1 = 2x , Q2-2xQ+1=0, Q 2x ± (2x) 2 − 4 Q1,2 = = x ± x2 −1 2 y 2 Q=ey → e = x ± x − 1 Ln(e y ) = Ln(x ± x 2 − 1) y = Ln(x ± x 2 − 1) = arc cosh x ± ifadesinde hem (+) hem (–) her ikisi de cozumdur. Pratikte + kullanilir. df -1 (x) 1 = df dx dx x → f −1 ( x ) Ters fonk turevleri. df -1 (x) 1 = df dx dx x → f −1 ( x ) Ters trigonometrik turevler. tan(arc tan x)=x sin(arc sin x)=x cos(arc cos x)=x P711): f(x)=x3, f -1(x)= x1/3, (f -1)'=? d ( x1 / 3 ) 1 1 1 = = = dx 3( x1 / 3 ) 2 d (x3 ) 3x 2 1/ 3 x→ x dx x → x1/ 3 (f-1)' =(1/3)x-2/3 Bildigimiz yontemle cozersek. [x1/3] ' =1/3 x1/3-1=1/3 x-2/3 bulunur. ---------------------------- ------------p772) f(x)=x2, (f -1)' =? 1 = 2 ( x )' x→ x 1 2 x x→ = x tan2 x =(tan x)2 tan x2 ≠ tan2 x tan2 (arc tan x) =[tan (arc tan x)]2 =x2 tan3 (arc tan x) =x3 sin2 (arc sin x) =x2 cos2 (arc cos x) =x2 df -1 (x) 1 = df dx dx x → f −1 ( x ) ( x )' = arc tan(tan x)=x arc sin(sin x)=x arc cos(cos x)=x sin (arc cos x) =? sin (arc tan x) =? tan (arc sin x) =? Bu durumda ic ve disi ayni yapmaya calisiriz. Once temel trigonometrik bagintilari hatirlamamiz lazim. 1 2 x Bildigimiz yolla cozersek. sin x sin x [x1/2] ' =1/2 x1/2-1=1/2 x-1/2 ------------------------p772) f(x)=x5+x, (f -1)' (2)=? f(x)=x5+x, f -1(x)=? f -1(x)bilmiyoruz. Hesaplamasi da kolay degil. Fakat soruda sadece f -1(x) in turevinin x=2 deki degeri soruluyor. df -1 (x) 1 = df dx dx x → f −1 ( x ) ( f −1 ( x ))' = 1 ( x + x )' = 5 x→ f −1 ( x) -1 1 (5 x + 1) = 4 x→ f −1 ( x) 1 , 5[ f ( x )]4 + 1 −1 f (2)=? x5+x=2, x=? x=1 koklerden birisidir. o halde f -1(2)=1 alabiliriz. 1 1 ( f ( 2))' = = , 4 5[1] + 1 6 −1 cos x 1 − cos 2 x cos x 1 − sin 2 x tan x tan x 1 + tan 2 x 1 1 + tan 2 x tan x sin x 1 − sin 2 x 1 − cos 2 x cos x p33) sin (arc cos x) =? sin (arc cos x) = 1 − cos 2 (arc cos x) = 1 − x 2 benzer sekilde p34) cos (arc sin x) = 1 − sin 2 (arc sin x) = 1 − x 2 p35) sin (arc tan x) =? sin x = tan x oldugundan 1 + tan x 2 sin (arc tan x) = tan(arctan x ) 1 + tan 2 (arctan x ) sin (arc tan x) = x 1+ x2 olarak bulunur. p37) cos (arc tan x)=? cos x = 1 1 + tan 2 x oldugundan cos (arc tan x) = cos (arc tan x) = 1 1 + tan (arctan x ) 1 2 1+ x2 421)f(x)=arc sin x ise f '(x)=? f -1 (x) 1 = df dx dx x → f −1 ( x ) f(x)=sin x, f -1(x)=arc sin x (arcsin x )' = = = = 1 (sin x)' x → arcsin x 1 cos x x→ arcsin x 1 cos (arcsin x ) 1 1− x2 422)f(x)=arc cos x ise f '(x)=? (arccos x )' = 1 (cos x)' x → arccos x = = = 1 - sin x x→ arccos x 1 - sin (arccos x ) 1 − 1− x2 423)f(x)=arc tan x ise f '(x)=? (arctan x )' = 1 (tan x)' x → arctan x = 1 (1 + tan x) 2 x→ arctan x = 1 (1 + tan (arc tanx) = 1 1+ x2 2