А. х²-4=0; х²=4; х=±2, true.
B. x²=-4; there is no solution.
C. 3x²+12=0; 3x²=-12; x²=-4; there is no solution.
D. 4x²=16; x²=4; x=±2, true.
E. 2(x-2)²=0; 2(x²-4x+4)=0; 2x²-8x+8=0; x²-4x+4=0; x1=2; x2=2. False. The answer: A, D.
Answer:
Step-by-step explanation:
Hi, We know:
Sin(a + b) = 2.Sin(a).Sin(b)
Then,
= 2Sin(a).Cos(b)/Cos(a).Cos(b)
Canceling Cos(b)
= 2Sin(a)/Cos(a)
As Tan(a) = Sin(a)/Cos(a)
Then we will stay:
= 2Tan(a)
Or
= Tan(a) + Tan(a)
There is anything wrong on the alternatives
Answer:
When two triangles are congruent they will have exactly the same three sides and exactly the same three angles. The equal sides and angles may not be in the same position (if there is a turn or a flip), but they are there.
