Question

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!ДАЮ 15 БАЛЛОВ!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Answer 1

Ответ:     8√3/9 .

Объяснение:

   v( t ) = s '( t ) ;       v( t ) = ( 1/cos²t )' = ( cos⁻²t )' = - 2cos⁻³t * ( cost )' =

                                       = 2sint/( cos³t ) ;     v( t ) = 2sint/( cos³t ) ;

  v( t₀ ) = v( π/6 ) = 2sin( π/6 )/[ cos³( π/6 )]  = ( 2 * 1/2 )/[ ( √3/2 )³ ] =

           = 1/( 3√3/8 ) = 8/( 3√3 ) = 8√3/9 ;   v( t₀ ) = 8√3/9 .