Recall that
sin(<em>a</em> + <em>b</em>) = sin(<em>a</em>) cos(<em>b</em>) + cos(<em>a</em>) sin(<em>b</em>)
sin(<em>a</em> - <em>b</em>) = sin(<em>a</em>) cos(<em>b</em>) - cos(<em>a</em>) sin(<em>b</em>)
Adding these together gives
sin(<em>a</em> + <em>b</em>) + sin(<em>a</em> - <em>b</em>) = 2 sin(<em>a</em>) cos(<em>b</em>)
To get 14 cos(39<em>x</em>) sin(19<em>x</em>) on the right side, multiply both sides by 7 and replace <em>a</em> = 19<em>x</em> and <em>b</em> = 39<em>x</em> :
7 (sin(19<em>x</em> + 39<em>x</em>) + sin(19<em>x</em> - 39<em>x</em>)) = 14 cos(39<em>x</em>) sin(19<em>x</em>)
7 (sin(58<em>x</em>) + sin(-20<em>x</em>)) = 14 cos(39<em>x</em>) sin(19<em>x</em>)
7 (sin(58<em>x</em>) - sin(20<em>x</em>)) = 14 cos(39<em>x</em>) sin(19<em>x</em>)
First seat: 14 candidates to seat
Second seat: 13 candidates to seat
Third seat : 12 candidates
4th seat: 11 candidates
5th seat: 10 candidates
6th seat: 9 candidates
Number of different variations: 14*13*12*11*10*9 = 2,162,160 different ways,
Observe that is 14P6 = 14! / (14-6)! = 14! / 8! = 14*13*12*11*10*9*8! / 8! =
= 14*13*12*11*10*9
Answer: 2,162,160
Answer:
You can use the Side-Angle-Side Postulate.
Step-by-step explanation:
The Side-Angle-Side (or SAS) Postulate basically states that if two sides of two triangles and the included angle are congruent, the two triangles are congruent.
Answer:
(a - 3b)(a + 3b)
Step-by-step explanation:
a² - 9b²
(a)² - (3b)²
(a - 3b)(a + 3b)
