How to find the derivative of trigonometric function? (sin ^ 2x) 'is the square of sin. How to find this? Similarly (COS ^ 2x) 'how to find this?

How to find the derivative of trigonometric function? (sin ^ 2x) 'is the square of sin. How to find this? Similarly (COS ^ 2x) 'how to find this?

Derivation of compound function
(sin^2x)`=2sinx(sinx)`=2sinxcosx
(cos^2x)`=2cosx(cosx)`=-2sinxcosx

Try to use the square difference formula to calculate: how much is the second power of 100 + the second power of 99 + the second power of 98 + the second power of K + 2 + the second power of 1

100^2—99^2+98^2—97^2+96^2—95^2+.+2^2—1^2=(100^2—99^2)+(98^2—97^2)+(96^2—95^2)+.+(2^2—1^2)=（100-99）（100+99）+（98-97）（98+97）+（96-95）（96+95）+...+(2-1)(2+1)=199+195+191+...+3=(199+3)*50...

Use the square difference formula to calculate (3 + 2) (square of 3 + square of 2) (4th power of 3 + 4th power of 2) (8th power of 3 + 8th power of 2)

(3+2)(3^2+2^2)(3^4+2^4)(3^8+2^8)=(3-2)(3+2)(3^2+2^2)(3^4+2^4)(3^8+2^8)=(3^2-2^2)(3^2+2^2)(3^4+2^4)(3^8+2^8)=(3^4-2^4)(3^4+2^4)(3^8+2^8)=(3^8-2^8)(3^8+2^8)=3^16-2^16

1 = 1 to the second power 1 + 3 = 2 to the second power 1 + 3 + 5 = 3 to the second power 1 + 3 + 5 + 7 = 4 to the second power. How much is 1 + 3 + 5... + 2009? Why? emergency

Law: 1 + 3 + 5 +. + (2n-1) = n ²
1+3+5……+2009=1+3+5+.+（2 × 1005-1）=1005 ²= one million ten thousand and twenty-five

1 / 2 power of 1

Any power of 1 is 1

Calculation: power - 1 of 2 + power - 2 of 2 + power - 3 of 2 + power - 4 of 2 +... + power - 100 of 2 Come on, let's go

a=2^(-1)+2^(-2)+……+2^(-100)
2a=2^0+2^(-1)+2^(-2)+……+2^(-99)
subtract
a=2^0-2^(-100)
That is, the original formula = 1-1 / 2 ^ 100