How Does (1+x)^r Compare to 1+rx for 0<r<1 and Specific x Values?

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~Sam~
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Homework Statement



Let 0< r <1. If x>0 or -1 less than or equal x <0. SHOW THAT (1+x) ^ r <1+rx


Homework Equations



no relevant equations


The Attempt at a Solution



I've tried isolating, but I can't relate x to x or r to r. I can't split the equation because I don't know r.
 
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Try using the binomial theorem to expand (1+x)r and then think about what 0<r<1 and -1≤x<0 really means for your expansion.
 
~Sam~ said:

Homework Statement



Let 0< r <1. If x>0 or -1 less than or equal x <0. SHOW THAT (1+x) ^ r <1+rx


Homework Equations



no relevant equations


The Attempt at a Solution



I've tried isolating, but I can't relate x to x or r to r. I can't split the equation because I don't know r.

"If x>0 or -1 less than or equal x <0."--->I think this statement has some problem.
 
blake knight said:
"If x>0 or -1 less than or equal x <0."--->I think this statement has some problem.

No there is no problem, it's X > 0 OR