Answer:
sin
/4 * sin/6 = 1/2 *(cos /12 - cos 5/12)
Step-by-step explanation:
Formula:- sinX sinY = (1/2) [ cos (X - Y) - cos (X + Y) ]
sin(π/4)sin(π/6)
= (1/2)[cos(π/4 - π/6) - cos(π/4 + π/6)]
= (1/2)[cos(3π/12 - 2π/12) - cos(3π/12 + 2π/12)]
= (1/2)[cos(π/12) - cos(5π/12)]
Answer:
11
Step-by-step explanation:
The two equations appear to be ...
- 12x +4y = 152
- 32x +12y = 420
These can be solved for y using Cramer's rule:
y = (152(32) -420(12))/(4(32) -12(12)) = -176/-16 = 11
The cost of the vegetarian lunch is 11.
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<em>Comment on Cramer's Rule</em>
For equations ...
ax +by =c
dx +ey = f
The solutions are ...
x = (bf -ey)/(bd -ea)
y = (cd -fa)/(bd -ea) . . . . note the denominators are the same expression
Once you memorize the pattern of products, this can be the simplest way to solve a pair of equations--especially if you only need one of the variable values.
Answer:
Isolate the variable by dividing each side by factors that don't contain the variable.
x = w/3 - 2/3
