Urgent!!! It is known that the opposite sides of the three inner angles A B C of the triangle ABC ar

From the known, according to the cosine theorem, we know that a=30°,(1):b=60°(2):s=1 4bc, and from the mean inequality we get bc<9 4, so the maximum value is 9 16

Answer: The triangular plexus is shaped by the loss of orange ABC satisfies:

asinasinb+b(cosa) 2=2a According to the sinusoidal theorem, there is:

a sina = b sin b=c sinc=2r so: sinb(sina) 2+sinb(cosa) 2=2sinasinb=2sina

Summary. Hello, is there a ** in this question!

In ABC, the three inner angles A, B, and C are paired by A, B, and B, respectively, and the remaining C, A (B-C) + BC 1Seek the size of a 2If a sina c 3, the circumference of abc.

Hello, is there a ** in this question!

No. The above is the answer I have based on the information you provided! Good.

On the second floor, don't just answer randomly, it just so happens that I did the math Zhou Lian and did the same problem. The landlord asked the first question correctly, but the second question was wrong, so give you the correct answer.

sin2a+sin2b+cos2c=1+sinasinb sin2a+sin2b-sinasinb=sin2c, using the sine theorem to simplify: a2+b2-ab=c2, that is, a2+b2-c2=ab, according to the cosine theorem: cosc=a2+b2?C22AB 12, c is the inner angle of the triangle, c=

3；(2) C=2, A2+B2-Ab=4, the area of ABC is 3

s△abc=1

2ab?sinc=3

ab=4 , which can be obtained by a=b=2

sin2a+sin2b+cos2c=1+sinasinb sin2a+sin2b-sinasinb=sin2c, using the sine theorem to simplify: a2+b2-ab=c2, that is, a2+b2-c2=ab, according to the cosine theorem: cosc=a2+b2?

c2 2ab 1 2 , c is the inner angle of the triangle, c = 3 ; (2) C=2, A2+B2-Ab=4, the area of Abc is 3, S Abc=1 2 Ab?sinc=3 , ab=4 , and a=b=2 can be obtained from