00:01
Hello, in this video, we will be solving the questions of a screen where in part one, we have to find out the range, amplitude, and period of the equation y equals minus 4, cos.
00:17
Inside cost, you have 3x and we have plus 2.
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First of all, let's look at the amplitude.
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Now the amplitude for any equation, let's say a cost bx plus c, your amplitude is always the absolute value of a.
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And therefore, in this example, our amplitude, i'm going to be am for short, is going to be four.
00:53
Very simply.
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Then for period, secondly, our period is always 180.
01:06
Or if you're talking in radiance or pi over b and so our period therefore will be 180 over 3 because we have 3x inside costs and so our period here will be equal to 60 60 degrees or simply pi over 3 if you're talking in radiance so this will be our period and finally for our range the range of any cost whatsoever is from minus 1 to 1.
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However, in this case, we have, first of all, a coefficient of negative 4.
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So our range automatically becomes from minus 4 to 4.
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However, we then also have a plus 2.
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And so our range becomes minus 4 plus 2, which happens to be minus 2, and 4 plus 2, which happens to be 6.
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And so our final range will simply be equal to y between, which happens to, and 4 ,000, between minus 2 and 6.
02:26
And so this is how you do the first part by simply stating the range amplitude and period of y equals negative 4 cost 3x plus 2.
02:36
In part 2, in question 2, we have to draw a couple of cycles for y equals minus 3 sine 2x plus 1.
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So here again, we have y equals minus 3 sine 2x plus 1.
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So let's first fall notice this plus 1.
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This plus 1 will provide us with a false axis.
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And this false axis is going to lie somewhere around here.
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Now i'm going to make a very rough diagram.
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It will not be exactly the way it's supposed to look, but it will be more than enough.
03:16
As for any sign graph, for any value of sine x, our graph goes from minus 1 to 1.
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However, again, with the coefficient of negative 3, our value here would be when multiplied by 3 or minus 3, it will grow from minus 3 to simply 3.
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And now finally, we have a plus 1.
03:52
1 will give us a range of minus 2 and 4, adding one on both sides...