Worked solution
Track five labelled points through eight transformations
The graph of is shown, with , , , and . On separate diagrams, sketch (a) , (b) , (c) , (d) , (e) , (f) , (g) , (h) . Indicate clearly, if possible, all coordinates of points corresponding to A, B, C, D and E.
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CJC · Transformations · Example 19
(a) Translate the whole graph right two
Answer
, , , , .
The Teacher asks that composite transformations and replacements be emphasised. Here replace x by : . The source gives the entire first transformed graph. All later coordinate calculations use the printed rounded B/D data consistently; they do not assert more precision for the underlying curve.
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(b) Reflect, then translate up one
Answer
, , , , .
Replace x by to get , then y by to get . Intermediate points are , , , , . The overall map is . Both originals print ; the x-coordinate must be 0.549 from the given B. Preserve that source typo in native/review evidence; the answer and reconstructed graph use 0.549.
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(c) Translate left, then halve horizontal distances
Answer
, , , , .
Translate left 1, obtaining ; then replace x by to obtain . The intermediate points are , , , , . The overall map is . The Teacher says this repeats Example 8 and need not be treated in detail again; reuse that replacement method while preserving both source diagrams and every coordinate here.
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(d) Mirror the right side, then double outputs
Answer
C gives ; D gives ; E gives . A and B are discarded.
First retain original inputs and reflect them to form . The intermediate D images are and E images , with C unchanged. Then replace y by : , hence . The source final plot has doubled heights 4.226 but is mislabelled ; preserve that typo in native/review text and label the actual final graph with its factor 2. Negative-input A/B are not carried into this construction.
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(e) Keep and mirror the original left side
Answer
A gives ; B gives ; C gives . D and E are discarded.
First reflect in the y-axis to obtain , with intermediate A′(1,0), B′(0.549,−0.631), C′(0,0), D′(−1.215,2.113), E′(−2,0). Retain the right-hand half of this reflected graph and mirror it to obtain . Equivalently, retain original inputs , then duplicate them symmetrically. The displayed intermediate and final source sketches are both retained.
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(f) Translate before taking output modulus
Answer
A gives , B gives , C gives , D gives , E gives .
Translate right 2 to obtain ; the intermediate coordinates are exactly those in part (a). Then reflect only the negative-output arcs in the x-axis, giving . The map is . B changes output sign; A/C/E stay on the axis and D stays above it. Both source stages and all coordinates are retained.
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(g) Translate the input-modulus graph right two
Answer
C gives ; D gives and ; E gives and . A and B are discarded.
First retain the original side and mirror it: has C(0,0), D-images and E-images . Then replace x by to obtain , symmetric about . For each retained input p, the two images have x-coordinates . At p0 the two images coincide, so C is counted once. This differs from taking output modulus in part (f).
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(h) Reciprocate non-zero outputs
Answer
, ; vertical asymptotes and horizontal asymptote .
A, C and E have zero outputs, so they have no finite reciprocal images and their x-coordinates become poles in the supplied continuous sketch. From the printed rounded data, and . B becomes a local maximum and D a local minimum. Preserve all four reciprocal branches and the original unbounded tail behaviour, giving horizontal limit 0. The reciprocal is undefined at 0, so it has no y-intercept; it has no x-intercept either. The source repeats the original given diagram beside this reciprocal, and both are retained.
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