How many times does the digit 7 appear among the terms of the sequence of consecutive integer numbers 7, 8, 9, ...., 777?
2 answers:
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The angle formed by the intersection of tangent and secant outside the circle equals half the difference of the <span>intercepted arcs.
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Easy, it says "for ANY positive integer" so just test any positive integer
remember that n! means times all integers from 1 to that number n
lets try 1
(1+1)!/(1!)-1=
(2!)/(1!)-1=
2/1-1=
2-1=
1
if you don't believe me, try 2
(2+1)!/(2!)-2=
(3!)/(2!)-2=
(6)/(2)-2=
3-2=
1
te answer is 1, B
and number 9
easy, remember the exponential law
(x^m)(x^n)=x^(m+n)
jsut add the exponents
first gropu like bases
(r^2r^2/3)(t^1/2t^-3/2)
add bases
(r^2 and 2/3)(t^-1)=
(r^2∛(r^2))(1/t)=
![\frac{r^{2} \sqrt[3]{r^{2}} }{t}](https://tex.z-dn.net/?f=%20%5Cfrac%7Br%5E%7B2%7D%20%5Csqrt%5B3%5D%7Br%5E%7B2%7D%7D%20%7D%7Bt%7D%20)
remember that n! means times all integers from 1 to that number n
lets try 1
(1+1)!/(1!)-1=
(2!)/(1!)-1=
2/1-1=
2-1=
1
if you don't believe me, try 2
(2+1)!/(2!)-2=
(3!)/(2!)-2=
(6)/(2)-2=
3-2=
1
te answer is 1, B
and number 9
easy, remember the exponential law
(x^m)(x^n)=x^(m+n)
jsut add the exponents
first gropu like bases
(r^2r^2/3)(t^1/2t^-3/2)
add bases
(r^2 and 2/3)(t^-1)=
(r^2∛(r^2))(1/t)=