Let f(x,y,z) = 5zxy+6x. Use this definition of to find the given functions.?

1.
f(x + 3y, x - 3y, 2x²)
= 5(2x²)(x + 3y)(x - 3y) + 6(x + 3y)
= 10x²(x² - 9y²) + 6x + 18y
= 10x⁴ - 90x²y² + 6x + 18y

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2.
f(6xy, 2y/x, 2xz)
= 5(2xz)(6xy)(2y/x) - 6(6xy)
= 120xy²z - 36xy

f(x,y,z) = 5zxy+6x

1.) f(x+3y, x-3y, 2x²) = 5(2x²)(x+3y)(x-3y) + 6(x+3y)
                                 = 10x² (x² - 9y²) + 6x + 18y
                                 = 10x⁴ - 90x²y² + 6x + 18y  ...................ANS

                                                         2y
2.) f(6xy, (2y)/x, 2xz) = 5(2xz)(6xy)( ----) + 6(6xy)
                                                          x
                                 = 120xy²z + 36xy  .........................ANS

f(x,y,z) = f(x+3y, x-3y, 2x^2) this means z= (x+3y) , x= (x-3y) and z = 2x^2

Just substitute to this equation 5zxy+6x , enter it then simplify.

The rest is just plain algebra.