-2ﺍﻟﻌﻼﻗﺔ ﺑﲔ ﺍﻹﻳﺮﺍﺩ ﺍﳊﺪﻱ ﻭﺍﻹﻳﺮﺍﺩ ﺍﳌﺘﻮﺳﻂ ﻭﻣﺮﻭﻧﺔ ﺍﻟﻄﻠﺐ ﻣﻦ ﺧﻼﻝ ﺍﻟﻌﻼﻗﺔ ﺍﳌﻌﻄﺎﺓ :ﺃﻧﻈﺮ ﺍﻟﺸﻜﻞ ﺃﺩﻧﺎﻩ )ﻟﻠﺘﻮﺿﻴﺢ(: ﺍﻟﻘﻴﻢ >1 =1 <1 0
ﺍﻟﻜﻤﻴﺔ
=
• ﻣﻼﺣﻈﺔ :ﺩﺍﻟﺔ ﺍﻹﻳﺮﺍﺩ ﺍﳌﺘﻮﺳﻂ ﻫﻲ ﺩﺍﻟﺔ ﺍﻟﻄﻠﺐ ﻷﻥ : ﻭﻣﻦ ﺧﻼﻝ ﺍﻟﻌﻼﻗﺔ:
=
ﳒﺪ:
= 1−
ﻣﺮﻭﻧﺔ ﺍﻟﻄﻠﺐ
.
=
=
ﺍﻹﻳﺮﺍﺩ ﺍﳊﺪﻱ
ﻣﺮﻧﺔ
<1
ﺳﺎﻟﺒﺔ
∆ ∆
ﻣﺘﻜﺎﻓﺌﺔ ﺍﳌﺮﻭﻧﺔ
=1
0
∆ ∆
ﻏﲑ ﻣﺮﻧﺔ
>1
ﻣﻮﺟﺒﺔ
∆ ∆
ﺍﻹﻳﺮﺍﺩ ﺍﳌﺘﻮﺳﻂ ﻳﻨﺨﻔﺾ ﻋﻨﺪ ﺍﺭﺗﻔﺎﻉ ﺍﻟﺴﻌﺮ، ﻭﻳﺮﺗﻔﻊ ﻋﻨﺪ ﺍﳔﻔﺎﺽ ﺍﻟﺴﻌﺮ. ﻻ ﻳﺘﻐﲑ ﻋﻨﺪﻣﺎ ﻳﺘﻐﲑ ﺍﻟﺴﻌﺮ. ﻳﺮﺗﻔﻊ ﻋﻨﺪ ﺍﺭﺗﻔﺎﻉ ﺍﻟﺴﻌﺮ، ﻭﻳﻨﺨﻔﺾ ﻋﻨﺪ ﺍﳔﻔﺎﺽ ﺍﻟﺴﻌﺮ.
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