Let a > 0, f (x) = x ^ 3 + ax ^ 2-9x-1, if the tangent of the curve y = f (x) with the smallest slope is perpendicular to the straight line x-12y = 0, then the real number b =?

f(x)=x^3+bx^2-9x-1
f'(x)=3x^2+2bx-9=3(x+b/3)^2-b^2/3-9
Therefore, the minimum slope of the tangent of the curve y = f (x) is - B ^ 2 / 3-9
The slope of the line x-12y = 0 is 1 / 12
According to the meaning, (1 / 12) (- B ^ 2 / 3-9) = - 1
B ^ 2 = 9, B = - 3 or B = 3
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It is known that the minimum value of even function f (x) defined on R is 1, and when x ≥ 0, f (x) = ex + A, where e is the base of natural logarithm (1), the analytic solution of function f (x) is obtained
It is known that the minimum value of even function f (x) defined on R is 1, and when x ≥ 0, f (x) = ex + A, where e is the base of natural logarithm
(1) Finding the analytic expression of function f (x)
(2) If the function f (x) = f (x) - bx2 has exactly two different zeros, find the value of B
(3) When x ∈ [1,3], f (x + T) ≤ X3 + 3x2 is constant, and the value range of T is obtained
Thank you

1: F (x) = e ^ x + a (x > = 0) if x = 0, f (- x) = e ^ (- x) + A is even function because x ∈ R, f (x) = f (- x) = e ^ (- x) + a (x = 0) f (x) = e ^ (- x) + a (x = 0) f (x) = e ^ (- x) (x0) f '(x) = e ^ x-2bx = 0 (ensure that f (x) has and has only one zero point when x > 0) BX ^ 2 = 2bx x x = 2, B = (e ^ 2) / 4

① (- 2) × (- 1 and 5 / 7) × (- 5 / 7)
② 3 / 4 × (8 - 1 and 1 / 3 - 0.04)

Original = - (2 * 12 / 7 * 5 / 7)
=-120/7
Original formula = 3 / 4 * (8-4 / 3-1 / 25)
=6-1-3/100
=5-0.03
=4.97

If A. B is a rational number and a = - B, then the relationship between the point representing a and the point representing B on the number axis is

The relationship between the point of a and the point of B: opposite numbers

3 (AX-2) - (x-1) = 2 (1 / 2 + x) if this equation has no solution, what is a equal to?

3ax-6-x+1=1+2x;
(3a-3) x = 6; no solution requires 3a-3 = 0, so a = 1

A good many; dozens of; a good deal of
To sum up all the similar phrases a good many; dozens of; a good deal of;
a number of………… And explain which is countable and which is uncountable

A great / big / large number of... A large number of (+ countable), as long as the number phrases are followed by countable nouns
A large number of (+ countable), as long as there are many phrases are followed by countable nouns
A great deal of
A great amount of... (+ uncountable)
Dozens / scores of many... (+ countable)
A bit of some (+ uncountable)
A lot of = lots of
A quantity of some,
A large quantity of (+ countable)
Many, many, many, many, many, many, many, many, many

Let AC = B, BC = a, ab = C, CD = h in △ ABC,
It is proved that (1) a & # 178; 1 / 1 + B & # 178; 1 / 1 = H & # 178; 1 / 1; (2) a + B ＜ C + H; (3) rt triangle with a + B, h, H + C as the edge

This is a * b = h * C, that is, a * b = h * C, that is, A-B = h * C, that is, A-B = h * C, that is, a \35;ᙧ5735;ᙧ35;5735;5735;5735;5735;35;##\35;\\\\\\\\\\\585858585858585858\\\\\\\\\\\\\\\\\\\65123; 178;, ﹣ 1 / a and﹣ 178; + 1 / b and﹣ 178; = 1 / h and﹣ 178

An English word or phrase that means "a lot."

1) A (large) number of / (large) numbers of + countable plural a number of birds have flowed to the south

What do WC, BBC, USA, am, WTO, ABC, PRC, PM mean

WC water closetbbc British Broadcasting Corporation USA United States of America a.m.anti meridian

The difference between give out and hand out

To give out; publish; give out
Hand out take out
It's very clear, landlord

Let a > 0, f (x) = x ^ 3 + ax ^ 2-9x-1, if the tangent of the curve y = f (x) with the smallest slope is perpendicular to the straight line x-12y = 0, then the real number b =?