A Cross/ Dot Product Question

I'm having trouble with this:

d1 = (3, -2, 4)
d2 = (-5, 2, -1)

Find:
(d1 + d2) . (d1 X 4d2)


d1 and d2 are vectors.

You can tell me the steps for solving this.
Thank you for your time.

d1 + d2 is (-2, 0, 3)
d1 X 4d2 is 4(ia2b3 + ja3b1 + ka1b2 - ia3b2 - ja1b3 - ka2b1)

=> d1 X d2 = 4[i(2) - i(8) + j(-20) - j(-3) + k(6) - k(10)]
=> d1 X d2 = -24i - 68j - 16k

(-2, 0, 3) . (-24i, -68j, -16k ) = 48 + 0 + (-48) = 0

Wolfram alpha gets 0. The above poster calculated the cross product incorrectly. It should be (-24, -68, -16).

Of course, you can also do this the easy way. (d1 + d2) . (d1 X 4d2) = d1 . (d1 X 4d2) + d2 . (d1 X 4 d2) = 4d2 . (d1 X d1) + d1 . (4 d2 X d2) = 4d2 . 0 + 4 d1 . 0 = 0 + 0 = 0, using the scalar triple product formula (see 2nd reference).

In my opinion the solution should be this:
(d1+d2)=(3-5,-2+2,4-1) = (-2, 0, 3)
(d1 X 4d2) = (3*(-20),(-2)*8,4*(-4)) = (-60, -16, -16)
Lastly
(d1+d2).(d1 X 4d2) = (120, 0, -48)