task/29453615
Вычислить : sin( arcsin 8/15 - arcsin 8/17 )
α = arcsin 8 / 15 ; β = arcsin 8/17
sin(arcsin8/15)*cos(arcsin8/17) - cos(arcsin8/15) *sin(arcsin8/17)=
* * *cosα= √(1 -(8/15)² ) =√(1 -64/225 ) =√(161/225 ) =(√161) /15 * * *
* * *cosβ= √(1 -(8/17)² ) =√(1 -64/289 ) =√(225/289 ) = 15 /17 * * *
sin(arcsin8/15)*cos(arccos(15 /17) - cos(arccos(√161) /15) *sin(arcsin8/17) =
8/15*15 /17 - (√161) /15 ) * 8/17 = (8/17)*(1 - (√161) /15 ).
(Х + 1) (x - 1) / (Х - 2)(x - 1) = (x² - 1) / (Х - 2)(x - 1) = (x² - 1) / (x² - 3x + 2)
2) (Х - 3) (x - 3)/ (Х + 3)(x - 3) = (x - 3)² / (x² - 9)
Х*(x + 3) / (Х - 3)(x + 3) = x*(x + 3) / (x² - 9)
3) (3 + Х)(x - 3) / (Х - 5)(x - 3) = (x² - 9) / (Х - 5)(x - 3) = (x² - 9) / (x² - 8x + 15)
Х*(x - 5) / (Х - 3)(x - 5) = Х*(x - 5) / (x² - 8x + 15)
4) (Х + 1)(x + 2) /x*(x² - 4) = (x² + 3x + 2) /x*(x² - 4)
x (4 + Х) / x( x² - 4)
task/29453615
Вычислить : sin( arcsin 8/15 - arcsin 8/17 )
α = arcsin 8 / 15 ; β = arcsin 8/17
sin(arcsin8/15)*cos(arcsin8/17) - cos(arcsin8/15) *sin(arcsin8/17)=
* * *cosα= √(1 -(8/15)² ) =√(1 -64/225 ) =√(161/225 ) =(√161) /15 * * *
* * *cosβ= √(1 -(8/17)² ) =√(1 -64/289 ) =√(225/289 ) = 15 /17 * * *
sin(arcsin8/15)*cos(arccos(15 /17) - cos(arccos(√161) /15) *sin(arcsin8/17) =
8/15*15 /17 - (√161) /15 ) * 8/17 = (8/17)*(1 - (√161) /15 ).