Question

what is the answer of
(x-3)(x+7)(x-4)=???

Answer 1

(x-3)(x+7)(x-4)
=(x^2+7x-3x-21)(x-4)
=(x^2+4x-21)(x-4)
=(x^3-4x^2+4x^2-16x-21x+84)
=x^3-37x+84

Answer 2

You can take the hard method to multiply again and again or you can choose this easy way.

According to the question
(x-3)(x+7)(x-4)

Here use this equation
(x-a)(x-b)(x-c) = x³-(a+b+c)x²+(ab+bc+ca)x-(abc) -------(equation 1)

Now in your question
make x-3, x+7, x-4 equal to 0
then you will get↓
a = 3
b = -7
and c = 4

Put those values in equation 1

•x³-(3+4-7)x²+[(3)(-7)+(-7)(4)+(4)(3)]x-(3*(-7)*4)

•x³-0x²+[(-21)+(-28)+12]x-(-84)

•x³-37x+84.

Easy, isn't it?
Believe me it will save you a lot of time. You can make mistakes in putting +,- in hard method but in this method, the chance of doing mistakes is very low.

Just remember that equation and when someone give you this type of ques just put values in it and it will be solved. No need of hard multiplying. If you find this hard, just try on your own by solving other problems of (x-a)(x-b)(x-c).
If you want to know how to solve (x-a)(x-b)(x-c)(x-d) then it will be

x⁴-(a+b+c+d)x³+(ab+bc+cd+da+bd+ac)x²-(abc+bcd+cda)+(abcd)

I hope you will find this helpful.
Mark this as Brainliest! :)