=4m？ + 12m+9-4m+20
=4m？ +8m+29
=4(m？ +2m+ 1)+25
=4(m+ 1)？ +25
∵(m+ 1)？ ≥0, so 4(m+ 1)? +25≥25 & gt； 0
That is, δ> 0, and the∴equation has two unequal real roots.
The bearing problem of balcony is urgent. I'm in the construction industry. I don't know how your construction skills are. Like your balcony, it must be a cast-in-place floor. If the weight of two tons is too big, if your balcony is a balcony, you'd better decorate your home to lose weight. If it is left for a long time, it will still be very bad. You should be able to reduce it to 1 ton and the stress distribution should be uniform.
Urgent, chemical problems, all want to turn red, CO2+H2O=H2CO3, generate carbonic acid to turn purple litmus red. It turns purple again, H2CO3=CO2+H2O.
Make clear lime water turbid.
CO2+Ca(OH)2 = = CaCO3↓+H2O
Photosynthesis, dry ice, sublimation, artificial rainfall, desertification
A few historical problems, urgent ~ ~1,d (it should be Wu Daozi)
13.C
14.A
15.b (Emperor Wendi of Sui Dynasty worships Buddha)
20 B
22 degrees celsius
23 D
25 amps
How to write a receipt-emergency receipt
What money did you receive from someone today?
Payee Name
date
Please note that the text and signature should not be too large. Easy to tamper with!
What's the third question? Emergency c
Urgent, hyperthyroidism problem? TSH is abnormally low. There is also palpitation and fatigue, indicating that hyperthyroidism is not completely controlled. Hyperthyroidism should be completely controlled, that is, there are no symptoms and TSH is normal, so that the maintenance amount can be changed. And sometimes you can't maintain one tablet a day, and you need two tablets to maintain it. I also especially recommend that you keep it for a long time, otherwise it will easily recur. I have a relapse again, and I have to start treatment from the beginning. It's right to gain 4 pounds. Hyperthyroidism is thin, hyperthyroidism has recovered, and weight should be restored.
I graduated from the third grade majoring in chemistry, but the work I am engaged in now has nothing to do with chemistry, and I have forgotten many things. After all, it's almost six years since graduation.
1. should be solute and solvent.
2. Temperature
3. Temperature
Wipe with alcohol. This method should be called extraction. The iodine used is more soluble in alcohol than in water.
Just put an egg in a physics problem. What can be suspended or floated is concentrated brine. According to Archimedes' law of buoyancy, buoyancy is equal to the density of liquid multiplied by g(9.8) multiplied by the volume of an object.
Everybody help me. Urgent! Urgent! Urgent! How to Speak Before Children Listen —— A Bible for Parents to Communicate with Children