Помогите с 238 и 237(в,г)

238)a)f'(x)=sin'(x³+x-π/4)=(cos(x³+x-π/4))*

(3x²+1)
f'(0)=cosπ/4=√2/2
b)f('x)=tg'(x²+π/6)=(1/cos²(x²+π/6))*2x
f'(0)=0

237)f'(x)=(tg³(2-3x))'=

3tg²(2-3x)*(1/cos²(2-3x))*
(2-3x)'=-9tg²(2-3x)/cos²(2-3x)


f'(x)=(ctg⁴(2x-1))'=

4*ctg³(2x-1)*(-1/sin²(2x-1)

*(2x-1)'=

-8ctg³(2x-1)/sin²(2x-1)