f x sin x 6 6 , the answer is f x 0, the latter is incomprehensible, ask for explanation

Make use of the auxiliary angle formula.

f(x)=sin(πx+π/6)

x [-1,1] t= x+ 6 [-5 6,7 6] then this is the image of the sint on [-5 6,7 6].

The zero point is the zero point of this image, and the highest point is the same, but you have to change back to x and it comes out.

Here's how to do it, please make the first to check the ginseng test:

If it helps, the reeds are destroyed.

Let y=e x, then the two sides of the hole key take the number of lead to the car of e.

lny=ln(e^x)=x;

x=lny;

f(y)=sin(lny) (e x=y,x=lny) so f( 2)=sin[ln( 2)]=sin(

Summary. 15 questions are C. The way to judge the continuity of a function at a certain point is from both sides of the x value, and the left and right limits of the function are equal to the function value of the function itself at this x point, then the function is continuous at this x point, which is obviously continuous.

According to the definition of the limit of the function, it can also be judged that the function is derivable, and the derivative is calculated to be 0.

Let f(x) = one part of sinx, then.

Hello, I have seen your question, can you send a specific question.

These three multiple-choice questions, 11-13-15

11 questions, 12 questions and 15 questions will do, thank you.

15 questions are C. The way to judge the continuity of a function at a point of a rock skin macro is from both sides of this x value, and the left and right limits of the function are equal to the function value of the function itself at this x point, so the function is continuous at this x point, which is obviously continuous. According to the definition of the limit of the function, it can also be judged that the function is derivable, and the derivative is calculated to be 0.

11 questions did not correctly answer the selection of the sail high item of the loose ruler case, is it a mistake to copy the sedan tomb? The method I use is to find f'(x)=-cos(1 x) x 2, when x=1 epoch in, f'(1/π)cos(π)2=π^2

12. Question A. The derivative of option a is -sin2x.

It's okay, it's a question copied by the counselor. Good.

Analysis: Because, the minimum positive period of the function f(x) cos( x 6/6) cos( x 6/6) sin x( 0, x r) is 2

f(x) cos( x 6/6) cos( x 6/6) sin x=2cos( x+6)=2cos(x+6).

Axis of symmetry equation: x+ 6=k ==>x=k - 6

Because f( )2cos( + 6) = 6 3==> cos( + 6) = 6 6

cos(2θ+π/3)=2(cos(θ+/6))^2-1=2*1/6-1=-2/3