4abc+13abc+ ___ +23abc = 0
Let the term to be filled in the blank be x.
Then, 4abc+13abc+x+23abc=0
⟹ x=0−4abc−13abc−23abc
⟹ x=0−4abc−(13+23)abc
⟹ x=−4abc−(1)abc
⟹ x=−5abc
What value of x makes the equation 4abc+13abc+x+23abc=0 true ?
Show that:
∑a3cos(B−C)=3abc
(or)
Prove that:
a3cos(B−C)+b3cos(C−A)+c3cos(A−B)=3abc