а ) y = x / cos ( x ) ; Производная у = ( у ) \' = ( x / cos ( x ) ) = ( x \' * cos x - ( cos x ) \' * x ) / cos ^ 2 x = ( 1 * cos x - ( - sin x ) * x ) / cos ^ 2 x = ( cos x - x * ( - sin x ) ) / cos ^ 2 x = ( cos x + x * sin x ) / cos ^ 2 x;б ) y = x / tg ( x ) ; Производная у = ( у ) \' = ( x / tg ( x ) ) \' = ( x \' * tg x - ( tg x ) \' * x ) / tg ^ 2 x = ( 1 * tg x - 1 / cos ^ 2 x * x ) / tg ^ 2 x = ( tg x - x / cos ^ 2 x ) / tg ^ 2 x = ( tg x * cos ^ 2 x- x * 1 ) / cos ^ 2 x ) / tg ^ 2 x = ( sin x * cos x- x ) / cos ^ 2 x * ( cos ^ 2 x / sin ^ 2 x ) = ( sin x * cos x- x ) * sin ^ 2 x ;в ) y = ( 4 x − 6 ) ^ 5 ; Производная у = ( у ) \' = 5 * ( 4 * x - 6 ) ^ 4 * 4 = 20 * ( 4 * x - 6 ) ^ 4.