(Pre)images of intervals #
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In this file we prove a bunch of trivial lemmas like “if we add a
to all points of [b, c]
,
then we get [a + b, a + c]
”. For the functions x ↦ x ± a
, x ↦ a ± x
, and x ↦ -x
we prove
lemmas about preimages and images of all intervals. We also prove a few lemmas about images under
x ↦ a * x
, x ↦ x * a
and x ↦ x⁻¹
.
Preimages under x ↦ a + x
#
@[simp]
@[simp]
@[simp]
@[simp]
Preimages under x ↦ x + a
#
@[simp]
@[simp]
@[simp]
@[simp]
Preimages under x ↦ -x
#
@[simp]
@[simp]
@[simp]
@[simp]
@[simp]
@[simp]
@[simp]
@[simp]
Preimages under x ↦ x - a
#
@[simp]
@[simp]
@[simp]
@[simp]
Preimages under x ↦ a - x
#
@[simp]
@[simp]
@[simp]
@[simp]
Images under x ↦ a + x
#
@[simp]
@[simp]
Images under x ↦ x + a
#
@[simp]
@[simp]
Images under x ↦ -x
#
Images under x ↦ a - x
#
@[simp]
@[simp]
@[simp]
@[simp]
Images under x ↦ x - a
#
@[simp]
@[simp]
@[simp]
@[simp]
Bijections #
theorem
set.Iic_add_bij
{α : Type u_1}
[ordered_add_comm_group α]
(a b : α) :
set.bij_on (λ (_x : α), _x + a) (set.Iic b) (set.Iic (b + a))
theorem
set.Iio_add_bij
{α : Type u_1}
[ordered_add_comm_group α]
(a b : α) :
set.bij_on (λ (_x : α), _x + a) (set.Iio b) (set.Iio (b + a))
@[simp]
Multiplication and inverse in a field #
@[simp]
theorem
set.preimage_const_mul_Iio
{α : Type u_1}
[linear_ordered_field α]
(a : α)
{c : α}
(h : 0 < c) :
@[simp]
theorem
set.preimage_const_mul_Ioi
{α : Type u_1}
[linear_ordered_field α]
(a : α)
{c : α}
(h : 0 < c) :
@[simp]
theorem
set.preimage_const_mul_Iic
{α : Type u_1}
[linear_ordered_field α]
(a : α)
{c : α}
(h : 0 < c) :
@[simp]
theorem
set.preimage_const_mul_Ici
{α : Type u_1}
[linear_ordered_field α]
(a : α)
{c : α}
(h : 0 < c) :
@[simp]
theorem
set.preimage_const_mul_Ioo
{α : Type u_1}
[linear_ordered_field α]
(a b : α)
{c : α}
(h : 0 < c) :
@[simp]
theorem
set.preimage_const_mul_Ioc
{α : Type u_1}
[linear_ordered_field α]
(a b : α)
{c : α}
(h : 0 < c) :
@[simp]
theorem
set.preimage_const_mul_Ico
{α : Type u_1}
[linear_ordered_field α]
(a b : α)
{c : α}
(h : 0 < c) :
@[simp]
theorem
set.preimage_const_mul_Icc
{α : Type u_1}
[linear_ordered_field α]
(a b : α)
{c : α}
(h : 0 < c) :
@[simp]
theorem
set.preimage_const_mul_Iio_of_neg
{α : Type u_1}
[linear_ordered_field α]
(a : α)
{c : α}
(h : c < 0) :
@[simp]
theorem
set.preimage_const_mul_Ioi_of_neg
{α : Type u_1}
[linear_ordered_field α]
(a : α)
{c : α}
(h : c < 0) :
@[simp]
theorem
set.preimage_const_mul_Iic_of_neg
{α : Type u_1}
[linear_ordered_field α]
(a : α)
{c : α}
(h : c < 0) :
@[simp]
theorem
set.preimage_const_mul_Ici_of_neg
{α : Type u_1}
[linear_ordered_field α]
(a : α)
{c : α}
(h : c < 0) :
@[simp]
theorem
set.preimage_const_mul_Ioo_of_neg
{α : Type u_1}
[linear_ordered_field α]
(a b : α)
{c : α}
(h : c < 0) :
@[simp]
theorem
set.preimage_const_mul_Ioc_of_neg
{α : Type u_1}
[linear_ordered_field α]
(a b : α)
{c : α}
(h : c < 0) :
@[simp]
theorem
set.preimage_const_mul_Ico_of_neg
{α : Type u_1}
[linear_ordered_field α]
(a b : α)
{c : α}
(h : c < 0) :
@[simp]
theorem
set.preimage_const_mul_Icc_of_neg
{α : Type u_1}
[linear_ordered_field α]
(a b : α)
{c : α}
(h : c < 0) :
theorem
set.image_mul_left_Icc'
{α : Type u_1}
[linear_ordered_field α]
{a : α}
(h : 0 < a)
(b c : α) :
theorem
set.image_mul_left_Icc
{α : Type u_1}
[linear_ordered_field α]
{a b c : α}
(ha : 0 ≤ a)
(hbc : b ≤ c) :
theorem
set.image_mul_left_Ioo
{α : Type u_1}
[linear_ordered_field α]
{a : α}
(h : 0 < a)
(b c : α) :
The (pre)image under inv
of Ioo 0 a
is Ioi a⁻¹
.