Solve math, don t rush the question if you re not sure

a(n)=s(n)-s(n-1)=2n^2+n-(2(n-1)^2+(n-1))=4n-1

a(n)=4n-1=4log2(b(n))+3

b(n)=2^(n-1)

a(n)*b(n)=(4n-1)*2^(n-1)=4n*2^(n-1)-2^(n-1)

Sum of split terms. t(n)=a(1)*b(1)+a(2)*b(2)+.a(n-1)*b(n-1)+a(n)*b(n)

4*1*2^(1-1)+4*2*2^(2-1)+4*3*2^(3-1)+.4*(n-1)*2^(n-1-1)+4*n*2^(n-1)-2^(1-1)-2^(2-1)

4*(1*2^(1-1)+2*2^(2-1)+3*2^(3-1)+.n-1)*2^(n-1-1)+n*2^(n-1))-2^(n)-1)

Let p(n)=1*2 (1-1)+2*2 (2-1)+3*2 (3-1)+.n-1)*2 (n-1-1)+n*2 (n-1) (1).

2*p(n)=1*2^(2-1)+2*2^(3-1)+3*2^(4-1)+.n-1)*2 (n-1)+n*2 (n+1-1) (2).

1)-(2):-p(n)=1*2^(1-1)+2^(2-1)+2^(3-1)+.2^(n-1)-n*2^(n)=(2^(n)-1)-n*2^(n)

p(n)=n*2^(n)-(2^(n)-1)

So t(n)=4*(n*2 (n)-(2 (n)-1))-2 (n)-1)=4*n*2 (n)-5*(2 (n)-1).

1.The angle p is equal to 65 degrees, and the angle p is equal to the angle A plus the angle d

2, I can't solve it...

3.Not true.

What about math problems that I can't do?

That's right, you miscalculated it when you substituted Equation 2. y=14 is substituted into equation 2 to get: 1 (14x)+2 3=1 (12x), i.e., 1 (12x)-1 (14x)=2 3, i.e.

1 12-1 14)*1 x=2 3, i.e. 1 84=2 3*x, then x=1 84 (2 3)=1 56You'll figure it out for yourself.

It is discussed in three situations:

b is an empty set. b=；

b=。

What about math problems that I can't do?

Hello, this question is actually quite simple:

Solution: original formula = 2012 2 - (2012-1) (2012 + 1) = 2012 2 - (2012 2-1 2).

Use a computer calculator.

Click Start - Programs - Accessories - Calculator in the lower left corner.

Cylindrical (2 ) 2*7 volume 8 +4 *7 surface area.

Cube volume 8*5*4 surface area 184

Conical volume 9 *15 3 Surface area 6 +9 *15 2

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