a、b、c、是三角形ABC三边,a、b、c、满足等式:b的平方=（c+a)(c-a),且5b-4c=0.求sinA+sinB的值

a、b、c、是三角形ABC三边,a、b、c、满足等式:b的平方=（c+a)(c-a),且5b-4c=0.求sinA+sinB的值
a、b、c、是三角形ABC三边,a、b、c、满足等式:b的平方=（c+a)(c-a),且5b-4c=0.求sinA+sinB的值

a、b、c、是三角形ABC三边,a、b、c、满足等式:b的平方=（c+a)(c-a),且5b-4c=0.求sinA+sinB的值
b的平方=（c+a)(c-a)=c^2-a^2 即c^2=a^2+b^2 ∴∠C=90°
又5b-4c=0 5b=4c b:c=4:5=sinB ∴ a:c=3:5=sinA
∴sinA+sinB=7:5

Because of the Christmas, the whole December were dyed profusion party season, the bells tolled, yet he growled carnival heat wave came. In the dance full of heat, champagne, people put beside the hea...

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Because of the Christmas, the whole December were dyed profusion party season, the bells tolled, yet he growled carnival heat wave came. In the dance full of heat, champagne, people put beside the heavy midwinter to toss clouds, calinton stream will be frivolous, shine, mini dress called to him. However, dressed casually BoLou is not easily become carnival through can focus. This one season, party animal in the "golden benchmarking will tacky" with the spring color bead piece, simple outline model with pink color, unexpectedly reveals how much tong qu, Proud queen with filar satin social choice with noble purple, fashionable tassel also jumped into their largely untouched by static also move, also, keep low-key missish, elegant have an eyelid. Princess skirt, scoop-back outfit, exaggerated glaring adorn article, the usual bestow favor on the leading role, supporting by burnish hind also in succession, a new play for dazzing female people of shaping different sides,true religion billy, also for this wonderful carnival season official blew countdown horn.
Each brand for the upcoming Christmas celebration developed a series of products. Adidas reprographic systems will be held recently released a series of X "mas Pack Christmas party series shoes, with adidas Superstar and classic Stan Smith two shoes type as the foundation. In the black color fastens vamp big play dazzling gold and silver totem changes,Asics Tiger, such as fill adidas Logo side gold and silver three line decoration, All white knitting vamp collocation heel gold silver offabrics, and combined with cream-colored and coffee shammy three wires on both sides of the gold and silver substrate,wholesale Jordan, etc., with low-key design feeling gorgeous in festive atmosphere.
In addition, adidas reprographic systems are more special launched with pink,Cartier Rings, pale green for ornament colour of all white Stan Smith shoes, including full of three leaves satin lining, lateral logo, heel shoe sole offabrics and wait, and let the girls nifty inadvertently exposed, quite match colourful Christmas party dress.
Affectionate zebra grain will always deduce infinite romance, not the winning but star red carpet is a magic weapon,true religion skirts, street pats da love most, the most direct is zebra grain nails, grab an eye but not ZaYan, make-up master can also in eyelash or eyeliner capitalize on, beautiful and novel. Enduring leopard grain, still in this year qiu dong show its irreplaceable high fashion, both eyes, lips, or with any part zygomatic, tell different sexy. Grasp the irregular elliptic grain, he grasped the Christmas party to meet the prince's initiative.
Will art absorbed makeup look no longer fresh, the fashionable pioneer socialist into makeup look is enough big, beautiful python grain is fashionable young senior purse, also can be the most chic Christmas party a makeup look, sounds very terrible, draw out but abnormal elegant.Topics related articles：


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