高一數學乘法公式:－new htc one開箱,htc手機評價,htc手機比較,htc手機遊戲,htc手機維修,htc手機價位,htc手機推薦,htc手機鈴聲,中華電信htc手機,htc手機截圖,亞太htc手機,

Blogtrottr

Yahoo!奇摩知識+ - 分類問答 - 科學常識 - 已解決

2013 Ski and Snowboard gear is on sale now.

Get ready for Spring with new arrivals and wake gear. Shop today.

From our sponsors

高一數學乘法公式

Oct 1st 2013, 14:10

得先知道 : (x+y)(y+z)(z+x)+xyz = (x+y+z)(xy+xz+yz)

然後開始做題目囉!

已知 x+y+z=(3+√7) / 2 , x^2+y^2+z^2 = (11+2√7) / 2

(x+y+z)^2 = x^2+y^2+z^2+2(xy+yz+xz) = 4+3√7/2

(x+y+z)^2 - x^2 - y^2 - z^2 = 2(xy+yz+xz) = (-3+√7)/2

得 : xy+yz+xz = (-3+√7)/4

故原式 : (x+y+z)(xy+xz+yz) = ((3+√7) / 2)((-3+√7)/4) = -1/4.....ans

---------------------
希望對您有幫助!

參考資料 mE

This entry passed through the Full-Text RSS service — if this is your content and you're reading it on someone else's site, please read the FAQ at fivefilters.org/content-only/faq.php#publishers. Five Filters recommends:

Massacres That Matter - Part 1 - 'Responsibility To Protect' In Egypt, Libya And Syria
Massacres That Matter - Part 2 - The Media Response On Egypt, Libya And Syria
National demonstration: No attack on Syria - Saturday 31 August, 12 noon, Temple Place, London, UK

You are receiving this email because you subscribed to this feed at blogtrottr.com.

If you no longer wish to receive these emails, you can unsubscribe from this feed, or manage all your subscriptions