It is known that the parabola Y = AX 2+BX+3 (A is not equal to 0) intersects with the X axis at points A( 1, 0) and B (-3,0), and educates the Y axis at point C (3 3,0) ... What a hurry! homework

(2) there are three. (-1, 6) or (-1, √ 10) or (-1, -√ 10).

(3) To maximize the area, where is the parabola? e？ Where is the tangent? BC? Parallel,

Because of the straight line? BC? What is the analytical formula of? y=x+3？ ,

Set it? e？ What is the tangent equation of? y=x+b？ , then by? -x^2-2x+3=x+b？ get

x^2+3x+b-3=0？ Let discriminant =9-4(b-3)=0? Have to? b=2 1/4？ ,

What is the solution of the above equation at this time? x=？ -3/2? , are substitutes available? y=x+b=？ -3/2+2 1/4= 15/4? ,

Namely. e？ The coordinates are (-3/2, 15/4).

A. What about the math teacher of Sixuejia Education, an extracurricular tutoring institution in Shenzhen?