Use the chain rule to find the indicated partial derivatives. z = x4 + x2y, x = s + 2t − u, y = stu2; ∂z ∂s , ∂z ∂t , ∂z ∂u when s = 4, t = 5, u = 1

to proof - by using the chain rule.

=

put the value of z, x and y.

we  get

now put the value of s=4, t= 5, u=1 in the above question.

now  by putting the value we get

 = 14236

now we find the

after doing differentiation

we get

now the put the value of x,y,z

we get

now we put the value of s=4, t=5,u=1

=19292

hence proved

now we find the value

now put the value of  x, y and z.

now put the value of u, v, z

we get

= -2548

hence proved

a) justify

step-by-step explanation:

justifying is just part of everyday life. justify kind of means proof so i think the answer is a) justify.

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