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Step * of Lemma rtan_functionality_wrt_rless

∀x,y:{x:ℝ| x ∈ (-(π/2), π/2)} .  rtan(x) < rtan(y) supposing x < y
BY
{ (InstLemma `rcos-positive` [] THEN Auto) }

1
1. ∀x:{x:ℝ| x ∈ (-(π/2), π/2)} . (r0 < rcos(x))
2. x : {x:ℝ| x ∈ (-(π/2), π/2)} 
3. y : {x:ℝ| x ∈ (-(π/2), π/2)} 
4. [%] : x < y
⊢ rtan(x) < rtan(y)

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Latex:

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Latex:
\mforall{}x,y:\{x:\mBbbR{}|  x  \mmember{}  (-(\mpi{}/2),  \mpi{}/2)\}  .    rtan(x)  <  rtan(y)  supposing  x  <  y


By

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Latex:
(InstLemma  `rcos-positive`  []  THEN  Auto)

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