1 00:00:00,810 --> 00:00:09,470 Simplify x y to the -2 power, times 2 x-squared over y-squared to the 4th power 2 00:00:09,485 --> 00:00:12,098 So let's see what we can do over here 3 00:00:12,098 --> 00:00:19,251 So let's think about this part of our expression first, if I have x over y to the n-th power 4 00:00:19,374 --> 00:00:24,346 we know that this is the same thing as, x to the n over y to the n 5 00:00:24,516 --> 00:00:26,401 So let's apply that right over here 6 00:00:26,401 --> 00:00:29,977 So this expression, 2 x-squared over y-squared to the 4th 7 00:00:29,977 --> 00:00:41,680 this is going to be the same as, 2 x-squared to the 4th power, over y-squared to the 4th power 8 00:00:41,680 --> 00:00:47,877 and of course we still have our x y to the -2 power out here, and actually let me simplify that as well 9 00:00:47,903 --> 00:00:54,267 we know that if we have, we know that if we have, x times y to the n-th power 10 00:00:54,267 --> 00:01:00,302 this the same thing as, taking each of the powers of each of the x and the y, and then taking the product 11 00:01:00,302 --> 00:01:04,203 this is x to the n times y to the n 12 00:01:04,203 --> 00:01:07,733 and actually if you just expand, if you multiply xy times itself n times 13 00:01:07,733 --> 00:01:09,869 we will see why this actually works out 14 00:01:09,869 --> 00:01:13,352 because you will have x multiplied by itself n times, if you rearrange the product 15 00:01:13,352 --> 00:01:15,952 and y multiplied by itself n times 16 00:01:15,952 --> 00:01:22,800 so if we use the same property here, x y to the -2, that's going to the the same exact thing as 17 00:01:22,800 --> 00:01:28,305 x to the -2 times y to the -2 18 00:01:28,305 --> 00:01:30,024 now, what can we simplify? 19 00:01:30,024 --> 00:01:34,668 well, we can use this property again, right over here, we have 2 x-squared raised to the 4th power 20 00:01:34,668 --> 00:01:38,918 so that's going to be the same as, that's going to the the same thing as 21 00:01:39,056 --> 00:01:45,519 2 to the 4th power, 2 to the 4th power times x-squared to the 4th power 22 00:01:45,796 --> 00:01:49,475 now we can do it in the denominator, y-squared to the 4th power 23 00:01:49,552 --> 00:01:51,804 Actually are going to use a different property in the denominator 24 00:01:51,804 --> 00:01:54,520 We just have y-squared to the 4th power 25 00:01:54,520 --> 00:01:59,606 We know that if we have x to the n, and then raise that to the m-th power 26 00:01:59,606 --> 00:02:02,857 this is the same as, x to the n times m 27 00:02:02,857 --> 00:02:06,943 so y-squared, and then raising that to the 4th power, that's going to be equal to 28 00:02:06,943 --> 00:02:12,874 y to the 2 times 4 power, or y to the 8th power. 29 00:02:12,981 --> 00:02:18,898 And of course out here, we have x to the -2 times y to the -2 30 00:02:18,898 --> 00:02:23,337 Now let's think a little bit about what x to the -2 and y to the -2 mean. 31 00:02:23,337 --> 00:02:31,620 x to the -2 just means 1 over x-squared, y to the -2 just means 1 over y-squared 32 00:02:31,620 --> 00:02:40,553 so let's rewrite it like that, this is the same thing as, 1 over x-squared times 1 over y-squared 33 00:02:40,553 --> 00:02:46,481 So we can just write that as 1 over x-squared, y-squared. That and that are completely equivalently 34 00:02:46,481 --> 00:02:51,479 So let's see what we can do now, so we have one last thing. Well we don't have one last thing 35 00:02:51,479 --> 00:02:52,919 we have a few more things to worry about 36 00:02:52,919 --> 00:02:56,267 we have x-squared and then we are raising that to the 4th power 37 00:02:56,267 --> 00:03:02,021 once again, we can use this property right here, this is going to be x to the 2 times 4 power 38 00:03:02,021 --> 00:03:08,383 so this part right over there, do it in a new color, this part right over here is going to simplify to 39 00:03:08,383 --> 00:03:12,238 x to the 8th power, 2 times 4 40 00:03:12,238 --> 00:03:19,250 this part right over here is going to, 2 to the 4th power, 2 to the 3rd is 8. So 2 to the 4th is 16 41 00:03:19,250 --> 00:03:25,613 so that is 16. and so our whole expression has now simplified to, if we multiply it times this 42 00:03:25,613 --> 00:03:29,467 we multiply it times 1, so i am going to multiply these 2 fractions. 43 00:03:29,467 --> 00:03:37,133 My numerator is 16 times x to the 8th, 16 times x to the 8th, and all of that over 44 00:03:37,133 --> 00:03:45,553 I have x-squared, I have an x-squared. And then I am going to have a y-squared times a y to the 8th 45 00:03:45,553 --> 00:03:49,530 what is y-squared times y to the 8th? y-squared times y to the 8th 46 00:03:49,622 --> 00:03:53,326 we have the same base, so we can add the exponents for taking the products 47 00:03:53,326 --> 00:03:57,888 so it's going to be y to the 2 plus 8, or y to the 10th power 48 00:03:57,888 --> 00:04:03,043 so y-squared times y to the 8th is going to be y to the 10th power 49 00:04:03,043 --> 00:04:06,067 and we are almost there, we have one more thing we can simplify 50 00:04:06,067 --> 00:04:11,588 we have x to the 8th over x-squared, and we know, I will just write the general property 51 00:04:11,588 --> 00:04:22,177 x to the m over, over, x to the n, this is equal to x to the m minus n power 52 00:04:22,177 --> 00:04:31,186 so x to the 8th over x-squared, that over there will simplify to x to the 8 minus 2 power 53 00:04:31,186 --> 00:04:33,786 or x to the 6th power 54 00:04:33,786 --> 00:04:44,223 and our whole expression has now simplified to 16, 16 times x to the 6th, times x to the 6th 55 00:04:44,223 --> 99:59:59,999 all of that over y to the 10th, and we are done