00:01
High from the question given that sine x is equal to 1 over 8 where x belongs to the first quadrant.
00:18
And if x lies in first quadrant means all the tritometry values are positive.
00:24
So first find cos x.
00:26
So we know that sine squared x plus cos squared x is equal to 1.
00:34
So from this, cos x is equal to under root of 1 minus sine squared x.
00:42
So here we have plus or minus symbol.
00:46
But we know that x is an first quadrant.
00:49
So in the first quadrant, all the trigonometry values are positive.
00:52
Therefore, cos x is equal to under root of 1 minus sine squared x is nothing but 1 over 8 the old square.
01:01
So this could be equal to square root of 64 minus 1 divided by 64.
01:09
So this is equal to square root of 63 divided by 8.
01:16
So from this, we know that cos x is equal to square root of 60p divided by 8 and sine x is equal to 1 over 8...