SOLUTION: Show that |a + b + c| <= |a| + |b| + |c| for all real numbers a, b, and c. Hint: The left-hand side can be written |a + (b + c)| . Now use the triangle inequali

Algebra ->  Graphs -> SOLUTION: Show that |a + b + c| <= |a| + |b| + |c| for all real numbers a, b, and c. Hint: The left-hand side can be written |a + (b + c)| . Now use the triangle inequali      Log On


   



Question 1207836: Show that
|a + b + c| <= |a| + |b| + |c|
for all real numbers a, b, and c.
Hint:
The left-hand side can be written
|a + (b + c)| .
Now use the triangle inequality.

Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.
Show that
|a + b + c| <= |a| + |b| + |c|
for all real numbers a, b, and c.
Hint:
The left-hand side can be written
|a + (b + c)| .
Now use the triangle inequality.
~~~~~~~~~~~~~~~~~~~~~

 
              Step by step


(1)  Make grouping  |a + b + c| = |a + (b + c)|.


(2)  Apply the triangle inequality

         |a + (b + c)| <= |a| + |b + c|.


(3)  Apply the triangle inequality again to the second absolute value addend

         |a| + |b + c| <= |a| + |b| + |c|.


(4)  Combine the steps into the final conclusion

         |a + v + c| <= |a| + |b| + |c|.


At this point, the proof is fully completed.

Solved, with complete explanation.