Answer:
$9.00
Step-by-step explanation:
Given that $1.8 is 20% of the breakfast cost.
-We can use proportions to find the 100% cost of the breakfast before the tip.
-Let x be the full breakfast cost:
Hence, the full breakfast cost is $9.00 before the tip.
Answer:
you're not doing anything wrong
Step-by-step explanation:
In order for cos⁻¹ to be a function, its range must be restricted to [0, π]. The cosine value that is its argument is cos(-4π/3) = -1/2. You have properly identified cos⁻¹(-1/2) to be 2π/3.
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Cos and cos⁻¹ are conceptually inverse functions. Hence, conceptually, cos⁻¹(cos(x)) = x, regardless of the value of x. The expected answer here may be -4π/3.
As we discussed above, that would be incorrect. Cos⁻¹ cannot produce output values in the range [-π, -2π] unless it is specifically defined to do so. That would be an unusual definition of cos⁻¹. Nothing in the problem statement suggests anything other than the usual definition of cos⁻¹ applies.
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This is a good one to discuss with your teacher.
Answer:
6
Step-by-step explanation:
66 / 6 =11
90/6 =15
11 & 15 prime to each other, so 6 is the answer.
