boyhiphop160
New Member
1-Cho tam jác ABC
Tìm max/min nếu có:
sin A.sinB.sinC ? max
cosA.cosB.cosC ? max
tgA.tgB.tgC ? min
cotg A. cotg B. cotg C ? min
____2_____2_____2
sin A .sin B . sinC ? max
___2____2____2
cos A .cos B .cosC ? max
___2____2____2
2- Chứng minh đẳng thức:
sina + sinb + sinc = sin(a+b+c) + 4.sin(a+b).sin(b+c).sin(a+c)
________________________________2______2______2
cosa + cosb + cosc = -cos(a+b+c) + 4.cos(a+b).cos(b+c).cos(a+c)
__________________________________2______-2_____-_2
3- Tính:
__1_____căn3 -----?
sin10___-cos10
tg3.tg17.tg23.tg37.tg43.tg57.tg63.tg77.tg83.tg243 ?
tg9 - tg27 - tg63 + tg81 ?
cos24 + cos48 + cos96 + cos72 ?
Tìm max/min nếu có:
sin A.sinB.sinC ? max
cosA.cosB.cosC ? max
tgA.tgB.tgC ? min
cotg A. cotg B. cotg C ? min
____2_____2_____2
sin A .sin B . sinC ? max
___2____2____2
cos A .cos B .cosC ? max
___2____2____2
2- Chứng minh đẳng thức:
sina + sinb + sinc = sin(a+b+c) + 4.sin(a+b).sin(b+c).sin(a+c)
________________________________2______2______2
cosa + cosb + cosc = -cos(a+b+c) + 4.cos(a+b).cos(b+c).cos(a+c)
__________________________________2______-2_____-_2
3- Tính:
__1_____căn3 -----?
sin10___-cos10
tg3.tg17.tg23.tg37.tg43.tg57.tg63.tg77.tg83.tg243 ?
tg9 - tg27 - tg63 + tg81 ?
cos24 + cos48 + cos96 + cos72 ?