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If the line X-Y + (3 ^ - 1) - 1 = 0 is rotated 15 degrees counterclockwise around points (1, 3 ^ - 1), the equation of the line L is?
y=√3*(x-1)+1/3
A straight line 2x-y-4 = 0 rotates 45 ° anticlockwise around its intersection with the X axis. The equation of the straight line obtained is______ ．
The slope of the straight line 2x-y-4 = 0 is 2; let the slope of the straight line be K, so tan45 ° = k − 21 + 2K = 1, so k = - 3, the intersection of the straight line 2x-y-4 = 0 and the X axis be (2, 0), so the straight line equation: y = - 3 (X-2), that is, 3x + y-6 = 0. So the answer is: 3x + y-6 = 0
Let the line 2x-y + 3 = 0 rotate 45 ° counterclockwise around the point (- 1,1) above it. The equation of the line is
I know the answer is 3x + y + 2 = 0, but I don't understand
Let Y-1 = K (x + 1), then there is | K-2 | / (1 + 2K) K
If you draw a picture, you can easily see it clearly; or imagine that the slope of the line before rotation is 2, and the positive angle between the line and the x-axis has exceeded 60 degrees. If you rotate it 45 degrees counterclockwise, the positive angle between the line and the x-axis must exceed 105 degrees, and the slope of the line will be negative
RELATED INFORMATIONS
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