Sách Toán – Học Toán – Đề Thi Toán https://booktoan.com Học toán, Đề thi toán, Sách giáo khoa Toán, trắc nghiệm Toán online Wed, 16 Sep 2026 02:45:11 +0000 vi hourly 1 https://wordpress.org/?v=7.1.2 Rút gọn biểu thức lượng giác $P = \frac{\sin a + 2\sin 3a + \sin 5a}{\sin 3a + 2\sin 5a + \sin 7a}$ https://booktoan.com/rut-gon-bieu-thuc-luong-giac-p-fracsin-a-2sin-3a-sin-5asin-3a-2sin-5a-sin-7a.html https://booktoan.com/rut-gon-bieu-thuc-luong-giac-p-fracsin-a-2sin-3a-sin-5asin-3a-2sin-5a-sin-7a.html#respond Wed, 16 Sep 2026 02:45:11 +0000 https://booktoan.com/rut-gon-bieu-thuc-luong-giac-p-fracsin-a-2sin-3a-sin-5asin-3a-2sin-5a-sin-7a.html https://booktoan.com/rut-gon-bieu-thuc-luong-giac-p-fracsin-a-2sin-3a-sin-5asin-3a-2sin-5a-sin-7a.html/feed 0 Rút gọn biểu thức lượng giác $P = \frac{\sin 4x – \sin 2x}{1 – \cos 2x + \cos 4x}$ https://booktoan.com/rut-gon-bieu-thuc-luong-giac-p-fracsin-4x-sin-2x1-cos-2x-cos-4x.html https://booktoan.com/rut-gon-bieu-thuc-luong-giac-p-fracsin-4x-sin-2x1-cos-2x-cos-4x.html#respond Wed, 16 Sep 2026 01:28:11 +0000 https://booktoan.com/rut-gon-bieu-thuc-luong-giac-p-fracsin-4x-sin-2x1-cos-2x-cos-4x.html https://booktoan.com/rut-gon-bieu-thuc-luong-giac-p-fracsin-4x-sin-2x1-cos-2x-cos-4x.html/feed 0 Cho hai góc nhọn $\alpha, \beta$ thỏa mãn $\tan \alpha = \frac{1}{2}$ và $\tan \beta = \frac{1}{3}$. Tính giá trị của $\alpha + \beta$ và biểu thức $P = \cos(\alpha + \beta) + \sin(\alpha – \beta)$ https://booktoan.com/cho-hai-goc-nhon-alpha-beta-thoa-man-tan-alpha-frac12-va-tan-beta-frac13-tinh-gia-tri-cua-alpha-beta-va-bieu-thuc-p-cosalpha-beta-sinalp.html https://booktoan.com/cho-hai-goc-nhon-alpha-beta-thoa-man-tan-alpha-frac12-va-tan-beta-frac13-tinh-gia-tri-cua-alpha-beta-va-bieu-thuc-p-cosalpha-beta-sinalp.html#respond Wed, 16 Sep 2026 00:38:10 +0000 https://booktoan.com/cho-hai-goc-nhon-alpha-beta-thoa-man-tan-alpha-frac12-va-tan-beta-frac13-tinh-gia-tri-cua-alpha-beta-va-bieu-thuc-p-cosalpha-beta-sinalp.html https://booktoan.com/cho-hai-goc-nhon-alpha-beta-thoa-man-tan-alpha-frac12-va-tan-beta-frac13-tinh-gia-tri-cua-alpha-beta-va-bieu-thuc-p-cosalpha-beta-sinalp.html/feed 0 Cho hai góc $a$ và $b$ thỏa mãn $\cos(a + b) = \frac{3}{5}$ và $\sin(a – b) = \frac{5}{13}$ với $0 < b < a < \frac{\pi}{4}$. Tính giá trị của biểu thức $P = \sin 2a + \cos 2b$ https://booktoan.com/cho-hai-goc-a-va-b-thoa-man-cosa-b-frac35-va-sina-b-frac513-voi-0-b-a-fracpi4-tinh-gia-tri-cua-bieu-thuc-p-sin-2a-cos-2b.html https://booktoan.com/cho-hai-goc-a-va-b-thoa-man-cosa-b-frac35-va-sina-b-frac513-voi-0-b-a-fracpi4-tinh-gia-tri-cua-bieu-thuc-p-sin-2a-cos-2b.html#respond Wed, 16 Sep 2026 00:32:25 +0000 https://booktoan.com/cho-hai-goc-a-va-b-thoa-man-cosa-b-frac35-va-sina-b-frac513-voi-0-b-a-fracpi4-tinh-gia-tri-cua-bieu-thuc-p-sin-2a-cos-2b.html https://booktoan.com/cho-hai-goc-a-va-b-thoa-man-cosa-b-frac35-va-sina-b-frac513-voi-0-b-a-fracpi4-tinh-gia-tri-cua-bieu-thuc-p-sin-2a-cos-2b.html/feed 0