If a,b,c,d are positive real numbers such that a + b + c + d = 2, then M = (a + b)(c + d) satisfies the relation

(a) : As A.M. >= G.M. for positive real numbers, We get ((a+b)+(c+d) / 2) >= [(a+b)(c+d) ]^1/2 M 0)Also (a+b)(c+d)>0$

If a,b,c,d are positive real numbers such that a + b... | Sequence & Series (Mathematics)

(a) : As A.M. $\geq$ G.M. for positive real numbers, $\\$ We get $\frac{(a+b)+(c+d)}{2} \geq[(a+b)(c+$ d) $]^{1/2}$ $\\$ $M \leq 1(\because a, b, c, d>0)$ Also $(a+b)(c+d)>0$

Explanation

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